CROCODILIANS, LIZARDS, AND SNAKES. 221 



The hepatic mesenteries conform to the general type, with certain 

 exceptions to be mentioned. Thus there are no right or left lateral 

 hepatic mesenteries, and but one ventral. The right hepatic supports 

 the right lung. There is frequently a rudimental right lateral hepatic, 

 which connects the long right apex of the liver with the right body 

 wall. There is a gastrohepatic which generally spreads caudad over 

 the space inclosed in the bend of the stomach. There is no left gastro- 

 parietal sheet or baud. The most remarkable deviation from this type 

 (which I have verified in twenty genera), is found in the Anolina. 

 Here the left lung, besides its superolateral connection with the stomach, 

 is connected by a special sheet with the left part of the inferior face of 

 the liver, forming the left gastroheiiatic. Thus the latter organ is 

 suspended by two sheets to the left side of the middle line. In genera 

 where this is the case the two sheets are sometimes difficult to distin- 

 guish, owing to their easy adhesion together. They may be separated 

 by inserting a probe from the free caudad extremity of the lung. 



Another variation from the normal type is seen in the presence of a 

 right lateral hepatic sheet in Phrynosoma and Polyehrns (in P. guttxrosus 

 it is wanting in the one specimen examined). A left lateral sheet is 

 present on the proximal half of the liver in Cyclura cornuta and Foly- 

 chrus marmoratus. It is rudimental in Polyclirus acutirostris, and want- 

 ing in P. giitturosus. There is a gastroparietal band in ('. cornuta.^ which 

 is joined by the apex of the peritoneum of the corpus adiposum. 



I have examined the hemiiienis in thirty species of this family of the 

 following genera : Anolis, Xqjhocercus, Polychrus, BaslUsciis, Ctenosanra, 

 Cyclura, Iguana^ Corythophanes^ Sauromalus, Grotapliytus, Dipsosaurus, 

 Liocephalus, Sceloporus, Callisaurus, HolhrooMa, Unyalioidcs, PorypJio- 

 riis, Microlophns, Uraniscodon, and Phrynosoma. These differ in the 

 bifurcation of the organ, varying from undivided {Cyclura, Iguana) to 

 deeply bifurcate (A?to?is', Doryphorus, j\Iicrolop]iu,s, Uraniscodon). Other 

 differences are seen in the number of the welts and their surface struc- 

 ture, and the distribution and size of the calyces. Thus tlie calyces 

 extend to the base in Anolis, but are confined to the apex in Crotaphy- 

 tus. They exist in series only in Cyclura, Iguana, Ctenosaura, Coryth- 

 oplianes, and Sauromalus. They cover most of the organ in Scelopo- 

 rus and Phrynosoma. The systematic arrangement of the genera in 

 accordance with the characters is as follows : 



I. Calyces always present. 



A. Three welts, oue opposite the sulcus spermaticus, aud one parallel on each 



side of it, transversely laminate. 

 Ctenosaura, Cyclura, Iguana, Coryihophanes, Sauromalus, Crotaphytua. 



B. Three welts, one opposite sulcus, the others one on each side of sulcus, con- 



verging to median welt and inclosing spaces with it. Surfaces 

 calyculate. 

 a. Welt confluent proximad. 



Dipsosaurus, lAoceplialuN, Phrynosoma. 

 aa. Welt projecting free proximad. 

 Callisaurus, Uolbrookia. 



