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Show 156 DR. R. W. SHUFELDT ON [Apr. 1, of a lens and carefully going over the region immediately over the parietal foramen, I failed to discover any external traces whatever of a "parietal eye," described by Spencer as existing in Sphenodon punctatum, and which has been found in so many Saurians since by other observers. Indeed, the tubercles are placed so close together on the top of the head in Heloderma, that a depression of any kind would be recognized at once. It is possible we may find something of the kind when we come to examine the brain in these specimens of mine. Passing to the ventral border of the thigh, ou either side, careful scrutiny failed to reveal to me any evidences of the pori femorales, that series of apertures which are the external openings of certain cutaneous glands in some Reptiles. Nor from an external examination do 1 find any evidences of the large anal glands, such as were found by Giinther to exist in Sphenodon. From an outer survey alone I would say that both of these specimens were females, but of course more extensive dissection will prove that point. Ossifications exist in the cutis of Heloderma, but the squamo-tuberculated skin of this reptile nowhere develops any special spines or similar appendages1. So far as I have been able to discover from the literature of the subject, little or nothing is as yet known of the reproduction of this lizard, beyond the fact that Captain Bendire, of the U. S. Army, found a number of eggs iu a specimen of Heloderma suspectum that he opened (60). Indeed, there still remains much that it is very desirable to know in so far as the habits of this reptile are concerned ; we may refer especially to the means it employs to secure its food, as well as the various kinds that go to make up its diet-list. W e find here and there authors referring to the nauseous odour emitted on the part of the Heloderma, and, although I have had them in captivity for a year or more together, I have never noticed any such characteristic as pertaining to them, aud I have studied them under a great variety of circumstances. Professor Garman has remarked that, " As if better protected from below, the Heloderma is said to turn himself ou his back when attacked." It never has been my fortune to have observed this habit in the case of Heloderma suspectum, and I am of the opinion that such is not the case with it. 1 Just here I would say that a year has passed by since this monograph was completed up to the above point, or where the index reference to this footnote occurs; during that time m y large specimen of the Heloderma has died and duly been placed in alcohol, while the writer's residence is no longer at Fort Wingate, N. Me.xico, but at his home a few moment's ride from Washington, D.C., where all the libraries and collections are open to him and easy of access. Through the kindness of Professor Gf. B. Goode, the director of the U. S. National Museum, I have also had placed at m y disposal another fine, large alcoholic specimen of the Heloderma suspectum from Arizona, as well as the loan of a handsomely mounted skeleton of the same reptile, from the collections of of that Institution. In view of these facts, I will not, in future pages of this memoir, refer to any particular specimen used in m y work; for it is sufficiently extensive now to obviate the necessity of that course ; with increased material comes a broadening of the field, permitting our passage from the description of a couple of specimens to more general obsarvations in the premises. |