68 Zoological Society. 



as before. It continued to live and increase in size for three weeks ;, 



when unfortunately some person trod upon the tail of the old one, 



which was protruded through the cage, a circumstance which caused 



its death in a few days : the young one died a few hours after, which I 



put into spirits. ,^ ^ ,, 



T Ti irr»i-iA 4. Too^7 "H. Cuming. 



Jagna, Isle of Bohol, August 1837. 



Among the collection sent by Mr. Cuming to the Society were 

 specimens of two species of Saurian ReptUes, upon which, at the 

 request of the Chairman, Mr. Martin offered some remarks. 



The first species to which he adverted was the Istiurus Amhoi- 

 nensis of Cuvier : two specimens of this rare reptile, both males, were 

 procured by Mr. Cuming in the Island of Negros. The Istiurus 

 Amboinensis, from the circumstance of the male being furnished with 

 an elevated crest or fan, supported by the spinous processes of the 

 base of the tail, in which respect it agrees with the Basilisk, was 

 placed by Daudin in the same genus with this latter reptile, and 

 characterized as the Basiliscus Amboinensis, and in this arrangement 

 Daudin was followed by most succeeding writers. So little allied, 

 however, in reality, are these two reptiles (though possibly they 

 may be the representatives of each other in different quarters of the 

 globe), that they belong to two different sections of the Sauria, of 

 which one has the Old World, the other the New World, for 

 its range. The Basilisk (Basiliscus mitratus, Daud.), with all the 

 American genera of the Iguanian group or Eunotes of Dumeril 

 and Bibron, belong to the section of that group termed Pleuro- 

 donta, distinguished by the situation of the teeth, which rise from 

 a furrow along the internal aspect of each jaw ; whereas the 

 Istiurus, with all the Old World genera of the Iguanian group, 

 (the genus Brachylophus , of which there is only one species, alone 

 excepted,) belong to the section termed Acrodonla, distinguished 

 by the teeth being firmly fixed along the very ridge of each 

 jaw, instead of having an insertion in a lateral furrow. Mr. 

 Martin observed, that the presence of the elevated fan at the base 

 of the tail, which occurs only in the males of Istiurus Amboinensis, 

 was a circumstance of interest, inasmuch as it involves a structural 

 difference between the osteology of both sexes. In the common 

 Water Newt, the male of which acquires fanlike membranes at a 

 certain season of the year, the membrane is unsupported by an 

 osseous frame-work, and is deciduous, or rather temporary ; but in 

 this animal, while the use of such a fan may be in all probability 

 connected with sexual functions, it is a persistent appendage. The 

 locality from which the specimens were derived gives them addi- 

 tional value. 



