PALEONTOLOGICAL PART 



PROLECANITIDAE Hyajt 



PROLECANiTiNAE Frech 



Daraelites Gemm. 



This genus was established by Gemmellaro^ for moderately involute, 

 smooth forms, with elliptical cross-section and a suture consisting of 

 entire rounded saddles and slightly serrated lobes. The siphonal 

 lobe is very wide and divided into three branches, the median of which 

 is extremely narrow, while the two lateral ones are broad and serrated 

 at the bottom. The external saddle is club-shaped, constricted at the 

 base, and rounded at the top. The first lateral lobe is less wide than the 

 preceding one, but deep and has a serrated bottom. The first lateral 

 saddle has the same form as the external one, but is much higher. The 

 second lateral lobe is much narrower and shallower than the first one, 

 but also serrated at the bottom. The second lateral saddle is a little 

 higher than half the first one, club-shaped, somewhat constricted at 

 the base, entire and rounded at the top. The rest of the lobes and 

 saddles are entire, rounded and directed obliquely backward. 



Gemmellaro compared his genus with Xenodiscus, Meekoceras and 

 Hungarites from the Permian of the Salt Range and Armenia, but at 

 the same time recognized that it had some relationship to Parapro- 

 norites. 



Although the evolution of the suture in Daraelites was unknown 

 at that time, Karpinsky^ demonstrated at once that this genus could 

 only be derived from Paraprolecanites. That his supposition was ab- 

 solutely correct has been shown much later by Tchernow^ who was 

 able to study the development of the suture. According to the figures 

 given by this author it is evident that the suture of Daraelites develops 

 from that of the so called Ibergiceras stage and passes through that 

 of Paraprolecanites''' and what by Tchernow is called the Prodaraelites 

 stage, and finally ends in the Daraelites stage. 



'Gemmellaro, Calc. c. Fusullna, p. 63. 



'Karpinsky, Amm. d. Artinsk-Stufe, p. 42, fig. 27. 



"Tchernow, L'Etage d'Artinsk, p. 371, et. seq., p. 297, pi. 1, fig. 9. 



'Tchernow calls this (explanation of his fig. 9-k) the beginning of the Daraelites stage. 



