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Glyptostrobus Endlicher is well represented in early Early Cretaceous to Pleistocene deposits in the middle to high latitudes of North America and Eurasia. Although the taxonomy and nomenclature of the genus is complicated, the fossil record indicates Glyptostrobus was represented by a small number of species. The genus first appears in Aptian age deposits from western Canada and Greenland, and achieved a wide distribution early in its evolutionary history. Exchange of Glyptostrobus between Asia and North America occurred across the Spitsbergen and Beringian corridors, which were functional about 110 and 100 million years ago, respectively The Late Cretaceous fossil record of Glyptostrobus shows that the genus had spread into Russia, China and the shores of the Turgai Strait. By the early Tertiary, Glyptostrobus was a prominent constituent of the polar broad-leaved deciduous forests. Paleocene age deposits across western Canada and the United States indicate the genus was present in great abundance in the lowland warm temperate and subtropical forests east of the Rocky Mountains. The broad distribution in North America and Russia during the Paleocene and Eocene indicates that Glyptostrobus grew and reproduced under a diverse range of climatic and environmental conditions, including the cold and unique lighting conditions of the polar latitudes. The presence of Glyptostrobus in Europe indicates the North Atlantic land bridges that extended between North America and Eurasia (Fennoscandia) and Europe during the early Tertiary were used. In Europe, extensive Glyptostrobus dominated swan1ps occupied the Central European Depression during the late Tertiary. Increasing global aridity and cooling, as well as landscape stabilization together with increasing competition for resources and habitat by representatives of the Pinaceae, seem to have forced the genus out of North America, Europe and most of Asia during the Miocene and Pliocene. In Japan, Glyptostrobus persisted until the early Pleistocene. After the early Pleistocene extinction in Japan, Glyptostrobus reappeared in southeastern China. Details of the taxonomic and biogeographic history of Glyptostrobus are examined.
This paper is a general review of the problem of clutch-size in birds. It grew out of a search through the literature to see to what extent clutch-size trends found in the Robin, Erithaau8 rebecula, might apply generally. Part I. describes those types of clutch-size variation found within any species, Part II. provides a general discussion of the factors involved. In Part IlI, which follows separately later, some of the differences between different species of birds will be considered. Examples are taken mainly from European birds, hence this review is in some ways supplementary to that on African birds by Moreau (1944), to which the present study owes a considerable debt.
(1) a. The mating behavior (including copulation) is described for the first time in the following species: Pardosa modica, P. emertoni, P. saxatilis, P. lapidicina, Lycosa helluo, .L. gulosa, Dolomedes scriptus, Phidippus clarus, P. audax, Philodromus pernix, and Coriarachne versicolor. b. The courtship only is described for the first time in Phidippus purpuratus. c. In Lycosa rabida and Pardosa milvina new data concerning the copulation, and in Schizocosa crassipes new data concerning courtship, are added to what is already available from Montgomery's work. d. In Tibellns oblongus and Xysticus triguttatus new data are added to the accounts of Gerhardt, and of Emerton, respectively. (2) a. On the basis of a large number of observations and experiments with the males of 19 species from 4 families of vagabond spiders, it is pointed out that the senses involved in courtship may vary with the species. b. There is no evidence that a sense of smell is used in sex recognition by any spiders. At least this sense plays no part in initiating courtship activity in the male. c. There is no evidence that Attid males can "recognize" the females by any sense other than sight. At any rate, it appears that the visual stimulus is the only one that suffices to incite courtship in this family. d. In one Lycosid observed, Pardosa emertoni, the courtship behavior is elicited only when the male can both see and touch the female. e. In the Pisaurid, Dolomedes scriptus, the sole stimulus for courtship is the chemoperception by contact of an ether-soluble substance normally covering the cuticle of the female. f. In the Lycosid, Pardosa milvina, the chemoperception by contact of an ether-soluble substance normally covering the cuticle of the female, together with the simultaneous perception of tactile stimuli will elicit courtship. This probably holds for P. saxatilis, Lycosa rabida, Schizocosa crassipes, and perhaps for Pardosa modica. Moreover, the sight of a moving Lycosid of about their own size may, in some cases, be sufficient for these males to start courting. g. In the Lycosids, Pardosa banksi, and probably Lycosn gulosa and L. helluo, only the simultaneous perception of both tactile and tacto-chemical stimuli suffices. Visual stimuli play no part in eliciting courtship. h. The condition in the Thomisids is in all probability similar to that in the preceding group of Lycosids. (3) a. In the case of those species in which contact chemoperception occurs it is shown that perception is not limited to the tarsi. Such stimuli can be perceived on all the segments of the legs as well as on the abdomen. From the known distribution of the slit sense organs it is probable that they are the chemoreceptors involved in courtship.
The seed collection of the species of the Gesneriaceae on which this study is based was obtained, for the most part, during a number of visits to the herbaria of the Smithsonian Institution, Washington, D.C., and the Royal Botanical Garden of Kew, London, and Edinburgh, Scotland. The seed collection comprises well over 800 samples of about 700 species of the Gesneriaceae, representing 113 genera of the 127 in the family, and provides a good taxonomic representation of the Gesneriaceae. Following an examination of all the samples in the seed collection, over 300 species of the 113 genera were selected to represent the wide range of seed morphology characters observed among the examined species of the Gesneriaceae. A system with which to analyze and diagnose seed surface morphology, designed by the author, is based on a format of six major categories and 60 tertiary terms of seed morphology characters and a companion diagnostic table. The categories are arranged in a sequence of increasingly smaller seed characters, ranging from seed shape to the ultrastructural characters of the individual cells. To ensure that the system would also apply to seed plants in general, the seeds, achenes and nutlets of a wide variety of species from families other than the Gesneriaceae were examined. Twenty species from 13 families other than the Gesneriaceae were then selected and are included in this study and, together with the Gesneriaceae, represent eight of the ten subclasses of the flowering plants (Cronquist 1968). The seeds, achenes and nutlets of all the species included in this study are illustrated with SEM photomicrographs on the 54 plates of the Seed Atlas, and the seed morphology data of each species are recorded on the diagnostic tables that face each of the Atlas Plates. To facilitate the comparison of the taxa of the Gesneriaceae, and to assist in the identification of the seeds of the examined species of the Gesneriaceae, the seed morphology data are also recorded on a summary table at the genus, tribe, subfamily and family levels. The seed morphology of the Gesneriaceae is compared and contrasted with the current classifications of the family at the species, genus, tribe, subfamily and family levels. The seed analysis system designed for this study has proven to be a rapid, efficient, uniform, objective method to deal with the analytical, diagnostic, and taxonomic aspects of an investigation of seed morphology. In addition, the system readily lends itself to the substitution or addition of terms and categories if needed, or to programming for a computerized analysis of seed morphology. It is hoped that the system will prove useful to other investigators, as well as prove helpful to standardize future investigations of seed
morphology.
The last decade of research in the field of animal nutrition has Ied to the discovery of a new class of substances in the food stuffs constituting the animal dietary. These compounds have been designated "Vitamines, Accessory Factors of the Diet, Exogenous Hormones of the Diet". They are present in infinitesimal quantities in certain articles of the diet, but their role in the metabolic cycle is one of the greatest importance. Subsequent investigation has shown that they are essential for the wellbeing and even the life of the organism itself. Without these indispensable elements the animal cell is unable to maintain its activities unimpaired, or the adolescent subject to attain normal growth. Continued deprivation leads to disease and ultimately to cessation of life. The discovery of these cornpounds was the result of a generation's work on the etiology of two diseases - Beri-beri and Scurvy. These are now known as "Deficiency Diseases". Each of these pathological conditions is due to the dietary deficiency of a specific substance, which in the case of beri-beri is known as the "Anti-neuritic Vitamin" (Funk); "Water Soluble B substance" (McCollum). In the case of scurvy this element is called the "Antiscorbutic Substance". A third factor associated with fats of animal origin has been subsequently discovered, but its deficiency results in a general malnutrition of a chronic type complicated with Xerophthalmia.
A cladistic analysis is presented of the hawkmoths of the tribe Acherontiini, Morgan´s Sphinx (Xanthopan morganii (Walker», and related genera. The study aims to test the monophyly of tribe Acherontiini; the hypothesis that all taxa with extremely long probosces (some Acherontiini, Meganoton rubescens, Neococytius, Xanthopan) form a monophyletic group, or at least fall within a single reasonably compact clade; and, within this group, to determine whether Xanthopan is more closely related to Acherontiini or to COCytillS and Neococytius. The data set comprises 109 characters derived from adult and immature stage morphology, biology and behaviour. These data were analysed using equal weighting, successive approximations character weighting (SACW) and implied weighting. All weighting schemes agreed on the monophyly of Acherontiini and of a group of genera comprising Amphimoea, Cocytius and Neococytius (the Cocytius group). Several other generic and suprageneric clades were also consistently recovered. However, those hawkmoths with extremely long probosces were never recovered as a monophyletic group. The relationships of Xanthopan were also ambiguous. Equal weighting and SACW placedXanthopan + Meganoton rztbescens (Butler) as sister to the COCytills group, while implied weighting placed Xanthopan as sister to Acherontiini. This latter relationship is based primarily on shared possession of a pilifer/palp hearing organ. Further analyses suggested the two components of this organ were not biologically independent. Downweighting this feature accordingly resulted in all weighting schemes converging on the topology found by equal weighting. Exclusion of the incomplete subset of immature stage data had no effect under implied weighting but equal weighting and SACW now recovered a Neotropical clade comprising Manduca. and the Cocytius group, while Xanthopan was placed with M. rubescens and Panogena. Downweighting the pilifer/palp hearing organ under implied weighting again caused convergence with the equal weighting/SACW results. Thus, the relationships of Xanthopan remain equivocal and further data, particularly from the immature stages, will be required to elucidate its phylogenetic position further.