| OCR Text |
Show 1890.] 0 HELODERMA SUSPECTUM. 157 Experiments made by a number of competent investigators during the past few years have satisfactorily demonstrated the fact to my mind that the venomous or non-venomous character of the bite of the Heloderma is placed beyond the peradventure of cavil, for there can be no doubt now but that its bite is soon fatal, at least to the smaller kinds of animals. Whether it has ever proved fatal in the case of man I believe still remains an open question, although I am inclined to believe that that, too, will sooner or later be substantiated. With respect to the affinities of the Helodermatidce, authors have entertained a variety of opinions; and, so far as I can ascertain, herpe-tologists are still considerably in doubt as to the position of these reptiles in the system, aud which group constitute their nearest kin. The opinion has been very generally held that the Heloderms are more or less nearly related to the Varanidce or perhaps to Iguanidce. Cope, in his recent work (61), places them as a family between the Xenosauridce and the Anguidce; while Gill (56) has created a superfamily for them, ranging it as the Helodermatoidea next above his superfamily the Varanoidea, and the Aniellidce, of his superfamily Anielloidea, immediately preceding them. Bocourt (34) recognizes the family Helodermidce, and " associates with it under the family Tr achy der mi, Wiegin., several lizards to which it offers considerable zoological affinities ; they differ from it in having smooth ungrooved teeth. Such a difference might at first seem to militate against their union with Heloderma, but this dental character, of great importance in the higher Vertebrata, has only a secondary importance among the Reptiles, as is exemplified by the serrated teeth of Macroscincus coctcei, D. & B." (Zool. Rec. 1878). A few years ago, Steindachner (35) described a new reptile from Borneo to which he gave the name of Lanthanotus borneensis, and which he claimed was related to the Heloderms. W e are, however, of the opinion that that fact is by no means a settled one. Nevertheless, Boulenger has placed the genus Lanthanotus after the family Helodej'matidce in the Catalogue of Reptiles in the British Museum (55), but remarks that " Whether the following genus is to be placed here, or constitutes a distinct allied family (Lanthanotida?, Steindachner), must remain doubtful until its anatomical characters are known. Its dentition was originally stated to be the same as in Heloderma, but this has been subsequently corrected by Steindachner." In the Catalogue we have cited, Boulenger has characterized the Helodermatidce for us in a masterly manner, and in the same place he presents us with the characters of Lanthanotus, so far as they are at present known from Steindachner's description. It is evident, then, that a complete account of the anatomy of this Bornean reptile, one of the supposed affines oi Heloderma, is very much to be desired; I am inclined to think, however, at present, that when its morphology comes to be fully known, its affinity with the Helodermatidce will not be found to be a near one by any manner of means, judging, as I do, from some of its external characters. PROC ZOOL. Soc-1890, No. XII. 12 |
