464 PROCEEDINGS OF THE ACADEMY OF [1896. 



In the genera Ctenosaura, Cyclura, Iguana, Sauromalus and 

 Enyalioides (latlceps) the organ is entire; in the others it is bilobate 

 or bifurcate. 



Of the Nyctisaura I have examined the hemipenis in the genera 

 Thecadadylus, Platydadylus, Phyllodactylus and Gymnodadylus. 

 In these this organ is short and wide, appropriately to the fragility 

 of the tail. It is also more or less deeply divided into two branches. 

 The entire surface is calyculate, generally minutely so. In Thecadac- 

 tylus each fork has three strong welts. In Platydadylus there is a 

 welt opposite the sulcus which is very large in P. aegyptiacus, and 

 divides, sending a half into each branch. In Gymnodadylus pul- 

 chellus the welts are not so heavy, below the bifurcation is a welt 

 which encloses a circular area which is incomplete proximad. In 

 Euhlepharis the hemipenis is closely similar to that of the Gecconidre. 

 It is short and deeply bifurcate ; it has a single prominent welt. 

 The surface of this is smooth, but the remainder of the surface is 

 calyculate. 



Of the Zonuridse I have only seen the hemipenis of Z. cordylus. 

 It is short and swollen, so that the spiral structure is accentuated ; 

 there is a rigid welt opposite the sulcus, which leaves a triangular 

 space at one side proximad, which is finely calyculate. On the oppo- 

 site side of the welt distad, is a wide space with radiating laminae 

 from a smooth center. The presence of calyculi noted is excep- 

 tional in the Diplogossa, and indicates approximation to the Pachy- 

 glossa as far as it goes. 



In the Anguidie the hemipenis presents well mai'ked characters, 

 which distinguish the genera and perhaps the subfamilies. In 

 Celest'us the extremity carries an osseous spicule of relatively large 

 size. Distad of the flounces are more (C. stenurus) or less (C 

 hadius) numerous longitudinal series of recurved osseous spines 

 which are longer near the sulcus sperm aticus. In C. stenuras the 

 flounces are apiculate at regular intervals ; organ undivided. In 

 the Gerrhonotinse the flounces are cupped and continue to the apex 

 without spines ; in Barissia and Gerrhonotus the organ is bifurcate, 

 in Elgaria simple. In Angtiisa. welt on each side of the sulcus has 

 tubercular cross-ridges, and the remainder of the surface is marked 

 with oblique folds with tubercular margins forming a chevron 

 which is directed distad. In Pseudojms apus the organ is not sym- 

 metrical. Opposite the sulcus is a low, broad, smooth welt, and on 

 each side the sulcus is margined by a thin welt or lip. This is 



