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Show 1882.] MR. W. A. FORBES ON THE GREAT ANTEATER. 289 with those of my predecessors, except as regards the number and openings of the ducts to the submaxillary glands, regarding which very different statements have been made at various times. Of these, Gervais's description, as given in some remarks accompanying the exhibition before the French Academy of Sciences of some models of these glands (C. R. s. ci), agrees best with m y observations. He says : - " Deux paires des canaux dont il s'agit viennent aboutir sepa-re* ment dans la bouche en se rendant a deux poches situees aupres de la symphyse mentonniere ; la troisieme paire verse un peu en arriere, egalement dans une petite dilatation terminale." A similar arrangement is described by J. Chatin in the genus Tamandua1, except that he says that there are two openings on each side at the symphysis. Pouchet, on the other hand, maintains (' Me'- moires ' &c. pp. v and 88) that there are only two ducts on each side, one of these being formed by the confluence of two of the three primary ducts coming from the corresponding three lobes of which each gland is composed. He oidy describes a single pair of openings close to the symphysis. Owen, finally, describes the three ducts of each side as eventually uniting, and opening, also by a single aperture, close to the symphysis. An examination, however, of his specimen (now preserved in the Hunterian Museum, where, by the kind permission of Prof. Flower, I was allowed to examine it), demonstrates the existence of a second pair of apertures in the floor of the mouth situated some 2 inches behind the first pair, which lie immediately behind the symphysis, in this respect quite agreeing with Gervais's description, and with my own observations on the second of m y (fresh) specimens (vide Plate XV. fig. 3 c). This second pair of apertures, which lie close to each other on each side of the median line and are very minute, are the openings of the deeper ducts, which, one on each side, arise from the more anterior (cervical) portion of the gland2. As these lie quite behind the other pair of apertures, any injection passed into the latter can of course only fill the two pairs of ducts (a, b) which debouch into them. This may easily explain, therefore, Pouchet's only having found two ducts on each side, though it is possible that individual specimens may vary in this respect. I must at least notice that in the first specimen that passed through my hands (the submaxillary ducts of which were injected from the anterior pair of apertures alone), I found on the left side a single duct only, and on the right two, which united together at about the level of the articulation of the lower jaw. This specimen, however, had, it is to be remembered, extensive inflammation in these parts, which may possibly have effected an alteration in the relations and number of the ducts. It is pretty clear, however, that three pairs all together is the ordinary number of these ducts, 1 Ann. Sci. Nat. 5, (Zool.) xiii. art. no. 9. 2 Such was, at least, the condition in the only specimen of Myrmecophaga in which these ducts had been satisfactorily injected examined by me. In Tamandua, according to Chatin's figure (op. cit. pl. 14), it is the ducts from the posterior (sternal) part of the gland that open here. This point requires reexamination, as also the number of apertures anteriorly. |
