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Show 120 ON THE ANATOMY OF HELODERMA. [Jan. 20, e. g. Varanus. The length of the continuation of the bronchus through lung-substance is 55 m m . The lung is 173 m m . long, the thin-walled rounded posterior end is the larger ; anteriorly the lung terminates in a blunt point. Dr. Shufeldt points out that in Heloderma the bronchi are long, but that Prof. Mivart states that they are short in Lacertilia. May not this discrepancy be due to the latter anatomist having measured from the bifurcation to the point of their entrance into the lungs, whilst Dr. Shufeldt included the prolongation into lung-substance 1 Kidneys.-If the kidneys of the large female H. horridum be compared with those of the somewhat small specimen of male H. suspectum, one is struck by the relative small size and more numerous lobulation of those of the former. They also show a marked distinction into an oval anterior region, and a tail-like posterior prolongation formed of from four to six small lobules closely adherent to the ureter. In H. suspectum the kidney gradually tapers to the posterior extremity. The length of the fore part of the kidney in H. horridum was 35 m m . ; its breadth 15 m m . ; the tail-region 15 m m . long. In the large male H. suspectum the kidney was 70 m m . long and 16 broad. Genitalia.-The genitalia of the male H. suspectum presented the ordinary Lacertilian features. The dorsal wall of the cloaca was provided with a couple of anal glands, whilst a belt of similar though smaller glands surrounded the ventral half of its circumference. The female H. suspectum was much the smaller of the three examples of the genus examined. In it the left ovary contained two nearly ripe ova, the right ovary three ; the largest ovum measured 24 m m . by 21 m m . Inferior labial Poison-glands.-The most interesting feature in the anatomy of Heloderma is probably the poison-apparatus figured and described by Fischer and Shufeldt. These both agree in stating that from the surface of each " submaxillary gland " nearest the lower jaw proceed from four to five ducts which pass into the sabstance of the jaw, and finally discharge the secretion of the gland at the bases of certain of the grooved teeth. This view of the structure I hold to be incorrect, and believe that the gland and its ducts are altogether external to the jaw ; that the ducts pass directly from the substance of the gland to their openings, which are situated to the inner side of a fold of mucous membrane which intervenes between the lip and the jaw. In H. horridum I only found one opening on either side, a guarded bristle could readily be passed through this into the upper of the three chief lobes of the gland ; and on injecting the substance of either lobe by means of a hypodermic syringe, the fluid escaped by this orifice alone. W h e n the gland of H. suspectum was similarly treated, the fluid in like manner freely flowed from all the four or five openings on the mucous surface, without a trace passing into the supposed ducts which went to the jaw, these being in m y opinion only the branches |