B7B Analytical Notices of Books. 



A third Herpetological Memoir derived from the investigation of the 

 treasures contained in the magnificent collection of the Leyden Museum, 

 is entitled, " Untersuchung der Speicheldriisen bei den Schlangen." Its 

 chief purpose is to make known an important fact in the economy of 

 certain snakes, in regard to which much uncertainty existed, their bite 

 having sometimes been found fatal, while at others it is perfectly harmless. 

 This anomaly is clearly accounted for by an observation first made by 

 Prof. Reinwardt on the Dipsas dendrophila of Java, afterwards extended 

 by Dr. Boie to other species of Dipsas and Homalopsis, and still further 

 confirmed in several other genera by M. Schlegel, the authour of the 

 present paper. All these snakes have teeth nearly similar in character to 

 those of the genus Coluber, excepting that the last on either side of the 

 upper jaw is longer than the rest, and has a deep sulcus on its anterior 

 surface, the base of which corresponds, as in the true poisonous fangs, 

 with the termination of the excretory duct of a poison-secreting gland. 

 As the sulcate poison-teeth stand much farther back within the mouth 

 than the fengs of Vipers, Rattle-snakes, &c, it is obvious that the danger 

 resulting from the bite of the snakes that possess them is contingent on 

 the extent to which the mouth is opened in the act of biting, or in other 

 words on the participation or non -participation of the hinder teeth in the 

 infliction of the wound. There exists a direct transition from the snakes 

 in question to the true poisonous snakes by the intervention of Elaps, 

 J^nja, Bungarus and Trimeresurus, in which the anterior portion of the 

 upper jaw is gradually shortened, the imperforate anterior teeth become 

 fewer in number, and the elongated posterior tooth is perforated as in the 

 Vipers, but has in addition an anterior fissure communicating with the 

 whole length of the cavity. These modifications are well represented in 

 a plate accompanying this important memoir. 



The only Ichthyological paper in the present volume is the commence- 

 ment of a " Vergleichende Betrachtung des starren Geriistes welches das 

 *' Fortpflanzungsgerathe tragt und umgiebt," by Dr. Ritgen. In this first 

 section of his prof>osed comparative osteology of the pelvis and its 

 auxiliary bones and cartilages, the authour confines himself, with the 

 exception of a few general observations, to the description of these 

 organs as they exist in Fishes, the lowest animals in which they can be 

 clearly demonstrated, unless we consider as the commencement of apelvis 



