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The avifauna of the island of Flores and its satellite islands from Komodo to Alor is reviewed, combining historical data with recent observations. Recent surveys have added substantially to the data base, especially of the resident forest species, and endangered and endemic taxa, as well as adding a number of migrant and maritime species to the island list. Of particular interest are the rare forest endemics Wallace's Hanging-parrot Loriculus flosculus, the almost unknown Flores Scopsowl Otus alfredi, Flores Monarch Monarcha sacerdotum and Flores Crow Corvus florensis. An appeal is made for further surveys over the eastern part of the island and the eastern island chain.
In the present revision of Sabia the number of species has been reduced from 55 to 19, including two that are described as new. Below the specific level, a new subspecies and a new variety are described, whereas some new infra specific combinations have been made. Most of the reduced species have been included in the synonymy of S. campanulata, which consequently represents the most complex and most variable species of the genus. Next to a general key, some regional keys are given as on the one hand some widespread species are locally far less variable than taken over their whole area, on the other hand well-delimited species from different regions may be very uniform in some points.
This paper is a monographic revision of tlie Holarctic genus Hilarimorpha Schiner. Twenty-seven species are recognized, twenty-two of which are new: Hilarimorpha abuta, bumulla, californica, clavata, cunata, desta, kena, lamara, Iantha, loisae, mandana, mentata, modesta, parva, pitans, punata, reparta, robertsoni, sidora, stena, tampa, and varda. Two described species from Asia, Hilarimorpha maculata and orientalis, are removed from the genus. In addition to a taxonomic revision of the genus, this study treats geographical distribution of the species, and the relationship of the genus to othe families of brachycerous Diptera.
1. Fomes applanatus, a perennial polypore of wide distribution and of common occurrence in North America and in Europe is responsible for the decay of very large quantities of wood annually. It attacks practically all deciduous species and several coniferous species, both dead wood and living trees. This fungus, heretofore commonly regarded as a pure saprophyte, has now for the first time been comprehensively studied; the investigations recorded in this paper have followed along three main lines of inquiry; (1) a study of the morphology and the ecology of F. applanatus and of the action on its host; (2) a determination of its etiological relationships by culture methods, and a testing of the applicability of such methods to a study of the timber destroying fungi; (3) an investigation of the possibility of finding criteria by which we may distinguish parasitic action on wood from saprophytic. 2. Fomes applanatus produces basidiospores only; conidia are not produced by the mycelium, nor, as is commonly affirmed, on the upper surface of the sporophore. The basidiospores are not of the ordinary type; each consists of a yellow, papillate, thick-walled chlamydospore within a thin hyaline wall. The so-called" truncate" base is in reality the apical end of the spore. Spore discharge is enormous and continues for by far the longest period recorded for fungi. It is continuous day and night for about six months-visible from vigorous fruiting bodies as spore clouds. Discharge is not affected by variations in light, humidity of the air, or temperature within very wide limits; frost causes an instant cessation and thereafter there is no further spore fall until a new set of pores is organized. The spores were not found to retain their viability for more than 6 1/2 months. They germinate in water and various other media within 48 hours after sowing, but the percentage of viable spores is very low and their behaviour with respect to germination is erratic. 3. No difficulty was experienced in culturing F. applanatus on artificial media or on wood. Three parallel series of cultures on wood were carried through to sporulation with mycelium obtained from (a) spores, (b) pieces of sporophore, (c) pieces of diseased wood. 4. Wood rotted by F. applanatus exhibits a mottled appearance sufficiently characteristic to permit of its recognition. when compared with other rots. In the case of living wood the area of attack is delimited by a wide dark band. Histologically, the decay is characterized by a perforation and corrosion of the elements culminating in disappearance of the tissues in localized pockets into which the mycelium gathers forming strands. Chemically, the change is one of delignification followed by a progressive solution of the resultant cellulose wall except for a few resistant fragments. In the later uniform white stage of decay, the threads of F. applanatus were always found to be accompanied by other destructive agentsbacteria or fungi. 5. The particular type of decay in timber due to Fomes applanatus has now been linked with its causal agent by actual culture. 6. Fomes applanatus has been proved to be a wound parasite, and in southern Ontario at least is one of the commonest and most destructive of this type. The proof rests on three grounds: (a) the conventional test applied to other such fungi-the mycelium works upward most readily by the way of the heartwood causing a characteristic decay and outward into the sapwood, eventual1y reaching the cambium, and is apparently the cause of the death of the tissues traversed by it; (b) a broad brown band is present in the wood of living trees along the advance line of the invading mycelium of this fungus. Within this band there is a copious production of brown wound gum and an excessive multiplication of tyloses; This band steadily moves fonvard with the advancing hyphae, the tyloses and wound gum being destroyed by the mycelium along its posterior margin as rapidly as they are formed along its antedor edge. The tyloses (and possibly the wound gum alsoJ certify to the living condition of the invaded tissues; their production can be ascribed only to the influence of the fungus, and the invasion of these tissues and their fate demonstrates directly its ability to act as a parasite; (c) inoculations with the spores and mycelium of F. applanatus into living trees resulted in an extensive browning of the inoculated wood with a multiplication of tyloses-both far in excess of similar phenomena due to traumatic stimulation. 7. The occurrence of wound gum and the multiplication of tyloses in a band marking the advance of a wood~destroying fungus in a living tree would appear to furnish an unerring criterion for the recognition of the fungus as a parasite.
1. The root tip of Cucurbita maxima possesses a single histogen from which all the primary root tissues arise. 2. The primary root is exarch, tetrarch. Differentiation of the large central metaxylem vessels is retarded; pith is not present. 3. The primordium of a secondary root is formed from the cortex, including the endodermis, as well as the pericycle of the primary root. 4. The transition extends from approximately 1 cm. below the peg to just above it. At the lowest level pith differentiates in the center and the metaxylem takes a peripheral position just within the phloem. Each primary xylem strand diverges into two arms extending laterally and joining the metaxylem. These arms separate, resulting in a siphonostele of four tangential transition bundles. These divide into two parts each, forming a total of eight bundles which become endarch. 5. Of these eight bundles usually two pairs anastomose, then divide into three, producing a total of ten bundles which continue through the hypocotyl. Additional bundles may arise. 6. The bundle is considered bicollateral on the basis of ontogeny; it shows a differentiation of internal phloem from the procambial tissue at the same time that the external metaphloem differentiates. (The study of a single species allows no interpretation on the basis of phylogeny.) 7. A suggestion is made concerning the differentiation of two types of phloem, the one called fascicular phloem and the other called connective phloem. Differences in origin, structure, and distribution of the two types are described. 8. In the cotyledonary node tangential anastomoses produce a cotyledonary plate of four parts. Continuations from these form two traces to each cotyledon. Before the cotyledon diverges completely, each trace branches laterally to form a basal vein from which arise four or more bundles which are the principal veins in the blade of the cotyledon. 9. The bundles of the epicotyl differentiate against the parts of the cotyledonary plate. The epicotyl is retarded in its development except for the median trace to the first foliage leaf. The early differentiation of this trace may account for the characteristic short first internode.
Birds are characterized by pneumatization of their skeletons by epithelial diverticula from larger, air-filled cavities. The diverticula-or 'air sacs'-that invade the postcranium result from outgrowths of the lungs; poslcranial pneumaticity has been very well studied. Much more poorly understood are the air sacs that pneumatize the skull. Study or craniofacial pneumaticity in modern birds (Neornithes) indicates the presence of two separate systems: nasal pneumaticity and tympanic pneumaticity, The lacrimal and maxillary bones arc pneumatized by diverticula of the main paranasal cavity, the antorbital sinus. There are five tympanic diverticula in neornithines that pneumatize the quadrate, articulare and the bones of the braincase. The pneumatic features of the following six genera of Mesozoic birds are examined: Archaeopteryx, Ellaliornis, Baplomis, Parahesperornis, Hesperornis and lchthyornis. Despite the 'archaic' aspect of most of these birds, many of the pneumatic features of neornithines are found in .Mesozoic birds and are considered primitive for Aves. The phylogenetic levels at which most of the avian pneumatic features arose within Archosauria are uncertain. Until the phylogenetic levels at which homologous pneumatic features arose are determined, it is unwise to use most pneumatic characters in the discussion of avian origins. Within avian phylogeny, Ornithurae and Neornithes are well-supported by pneumatic synapomorphies. There is a trend towards reduction of craniofacial pneumaticity within Hesperornithiformes. Witthin Neornithes, four derived pneumatic characters suggest that the Palaeognathae (ratites and tinamous) is monophyletic.
Homology of virtually all major components of facial anatomy is assessed in Archosauria in order to address the function of the antorbital cavity, an enigmatic structure that is diagnostic for the group. Proposed functions center on its being a housing for a gland, a muscle, or a paranasal air sinus. Homology is approached in the context of the Extant Phylogenetic Bracket method of reconstructing unpreserved aspects of extinct organisms. Facial anatomy and its ontogeny was studied in extant archosaurs (birds and crocodilians) to determine the osteological correlates of each soft-tissue component; resemblances between birds and crocodilians comprised the similarity test of homology. The congruence test of homology involved surveying phyiogenetically relevant fossil archosaurs for these bony signatures. The facial anatomy of extant birds and crocodilians is examined in detail to provide background and to discover those apomorphic aspects that contribute to the divergent specialization of these two groups and thus obscure homologies. Birds apomorphically show enlarged eyeballs, expanded nasal vestibules, and reduced maxillae, whereas crocodilian faces are dorsoventrally flattened (due to nasal rotation) and elongated. Most facial attributes of archosaurs are demonstrably homologous and in fact characterize much more inclusive groups. Special emphasis has been placed on the nasal conchae and paranasal air sinuses. Within Amniota, the following conchal structures are homologous, and all others are neomorphs: avian caudal concha, crocodilian concha + preconcha, Sphenodon caudal concha, squamate concha, and probably the mammalian crista semicircularis. The avian antorhital paranasal air sinus is homologous with the crocodilian caviconchal sinus; the maxillary sinus of placental mammals is not homologous with the archosaurian paranasal sinus. With regard to the function of the antorbital cavity, archosaurs possess homologous nasal glands, dorsal pterygoideus muscles, and paranasal air sinuses, but the osteological correlates of only the paranasal sinus involve the antorbital fenestrae and fossae. Thus, the antorbital cavity is best interpreted as principally a pneumatic structure.
The specimens which form the basis of the following notes and descriptions were received by the writer from Mr. Ch'i Ho, Asistant Entomologist of Fan Memorial Institute of Biology, who collected thern either in Peiping or Eastern Tomb (40.2 N, 117.0 E), Hopei Province. They belong to nineteen species and are included in fifteen genera. Two of the species are believed to be new to science.