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Show 474 PHOF. G. GULLIVER ON [Juiielo, prehensile claws, it would be impossible for them to mount trees without this special provision for climbling. In Tylonycteris and Glischropus the fleshy foot-pads without doubt perform similar functions, probably enabling these Bats to cling to the under surfaces of large leaves and fruits, perhaps not so effectively, however, as the much more highly specialized pedunculated sucking-disks of Thyroptera tricolor enable that animal to adhere to smooth surfaces as securely as a fly. 2. Observations on the Sizes and Shapes of the Red Corpuscles of the Blood of Vertebrates, with Drawings of them to a uniform Scale, and extended and revised Tables of Measurements. By G E O R G E G U L L I V E R , F.R.S., late Professor of Comparative Anatomy and Physiology to the Royal College of Surgeons. [Received May 31, 1875.] (Plate LV.) No physiologist is likely at the present day to undervalue, as John Hunter did, the importance of the red blood-corpuscles. They often afford valuable characters which, though regularly ignored in the books of systematic zoology, should always form a part of the descriptions of the orders, and sometimes of the species, of each class of vertebrate animals. Higher still is the physiological significance of the corpuscles ; their relations of individual size and of aggregate proportions to the other constituents of the blood, and to the economy of the species (in which we now know that the corpuscles perform an important function intimately connected with their size and number), have become questions of much interest and moment which still require further investigation. But such inquiry would be foreign to the present purpose, which is to give simply the averages, with brief explanatory comments, of numberless measurements, all made by me, in the hope that they may be useful towards further researches of the same kind. And so many are the facts either suggested or shown by my Tables, in relation to the significance of the comparative sizes of the corpuscles, that I can here make no attempt to consider or develop this branch of the subject, It has been admirably treated by Professor Milne-Edwards in his ' Lecons sur la Physiologie et 1'Anatomie Comparee,' and was summarily noticed in m y ' Lectures on the Blood, Lymph, and Chyle,' delivered at the Royal College of Surgeons, and reported (with engravings) in the ' Medical Times and Gazette,' 1862-3. On the taxonomic import of the nucleus of the red corpuscle, m y observations (illustrated by woodcuts drawn to a scale) are published in the «Proceedings' of this Society (P. Z. S. 1 862, p. 91, et 1870, p. 92) |