OCR Text |
Show 580 MR. R. B. SHARPE ON CERTAIN ACCIPITRES. [Nov. 3, all my then measurements of the red corpuscles in this order of Phoca proved the largest; and now this size is exceeded in Otaria and Trichechus. The smallest red blood-corpuscles in the Carnivora occur in some species of Fiverra, Paradoxurus, and Herpestes. But between several sections of this order there are curious irregularities in the differences of the size of these corpuscles, which, as our knowledge extends, will probably prove of physiological significance : meanwhile I have already shown that they have taxonomic value ; for example, by the comparative magnitude of the red blood-corpuscles alone the Canidae may be easily distinguished from Viverridae. Trichechus rosmarus.-This animal (the Morse orWalrus of popular books) has the red blood-corpuscles still larger than those of the Eared Seal. Some years ago a young Walrus arrived in a sickly state, and died soon afterwards, at the Society's menagerie, when I examined its blood and found it very rich in red blood-corpuscles, and consequently of high specific gravity. Referring to my notes, it appears that the mean of numerous measurements of the diameter of the corpuscles was ^yH-^ of an inch, being exactly the same as the average diameter of the corresponding corpuscles of the two great Edentates already mentioned. And this conclusion is confirmed by recent measurements of the old specimens of the blood-corpuscles of Trichechus; they were so long since dried, and yet are still beautifully perfect. Thus of all apyrenaematous red corpuscles, those of Elephas, Myrmecophaga, Orycteropus, and Trichechus are the largest at present known. The red blood-corpuscles of man are among the largest of the Mammalia. No British animal of this class has them so large ; in all my former observations red corpuscles distinctly larger than of man were found only in six Mammalia, to wit, Myrmecophaga jubata, Orycteropus capensis, Bradypus didactylus, Elephas indicus, africanus, and Balana boops. To these must now be added Trichechus rosmarus and Otaria jubata. Structure and Form.-The red blood-corpuscles of the Hippopotamus, Otaria, and Trichechus conform in structure and shape to the regular apyrenasmatous type. Nor among the Mammalia has any indubitable exception to the apyrenaematous character of these corpuscles yet been found. 4. Contributions to a History of the Accipitres or Birds of Prey. By R. B O W D L E R SHARPE, F.L.S., F.Z.S., & c , of the Zoological Department, British Museum.-I. On the Females of the C o m m o n and South-African Kestrels. [Received August 5, 1874.] (Plate LXVIII.) A short time ago I received from my friend Mr. Bygrave Wharton a pair of Common Kestrels which he had recently obtained in Hert- |