78 



kept in a constant position the embryo may appear on any side of the 

 eo-g and with its axes pointed in any direction. I have seen cases in 

 which parts of the embryo were involved in the enfolded lips of the 

 blastopore. Such parts then apparently failed to develop , while the 

 parts lying freely on the surface appeared to be nearly normal. 



Whatever may be the cause for this abnormal method of develop- 

 ment, it is important to recognize that apparently insignificant changes 

 in external conditions are capable of producing profound modifications 

 of the normal methods of growth. 



The facts here described are, to my mind, very suggestive. I see 

 in them not retrogressive variations indicating conditions in ancestral 

 types. They indicate rather the direction of flexibility of the organism 

 under the stress of a new environment. They may be regarded as pro- 

 phetic of the variations to occur in the descendants of Limuloid Ar- 

 thropods that might culminate finally in the normal meroblastic egg 

 and »yolk blastopores« of vertebrates. 



These facts may be regarded as constituting a part of the indirect, 

 or circumstantial evidence of the relation ship oïLimulus to the verte- 

 brates. If, in other words, the eggs of Linmlus under abnormal con- 

 ditions segment meroblastically and develop »yolk blastopores« like 

 those of Ganoids and Amphibia, it is almost certain that if these un- 

 usual conditions become constant then the result of these conditions, 

 i. e., meroblastic segmentation and a yolk blastopore, would also 

 become constant. 



Dartmouth College, Dec. 2üth 1893. 



4. Beiträge zur Herpetologie Transkaukasìens und Armeniens. 



Von L. V. Méhely, Brassó (Ungarn). 



eingeg. 11. Januar 1894. 



Der Freundlichkeit des Herrn Dr. G. von Horväth verdanke 

 ich eine kleine Collection Batrachier und Reptilien aus Transkaukasien, 

 die er im Monate Juni 1893 theils in der Gegend von Tiflis, Eriwan 

 und Evirili, theils in Aralich, am Fuße des Ararat gesammelt hat. 

 Trotzdem, daß die Zahl der zusammengebrachten Arten kaum ein 

 Fünftel der von Keßler in seiner Arbeit von 1878 aufgezählten Arten 

 Transkaukasiens ausmacht, dürften diese Zeilen doch manchen Bei- 

 trag zur eingehenderen Kenntnis der hier behandelten Thiere enthalten. 



I. Batrachier. 



1) Rana esculenta L. var. ridibunda Pall. 

 Boettger in Eadde's Fauna und Flora d. s.-w. Caspigebiets, 

 Leipzig 1886, p. 76. Boettger, Wissensch. Erg. d. Reise Dr. J. 



