Figure 4. Stelgistrum concinnum Andriashev, type from off Cape Olytorsky 



consider those examples with a short and blunt snout to be closer to the subspecies 

 described by P. Y. Schmidt (1929) as Triglops pingeli pacificus from the Bering 

 and Okhotsk Seas. It is perhaps too early to delimit its distribution as the 

 former researchs by (P. Y. Schmidt 1929, and others) do not include the sub- 

 species Triglops ommatistlus and T. s. terraenovae , described by Gilbert from 

 the Atlantic coasts of North America .1./ These two forms are related to each as 

 the T. beani Gilbert and T. metopias Gilbert and Burke, (the main differences 

 lie in the number of lateral folds) and are very close to T. beani from the Pacific 

 Ocean, which complicates the systematic position of T. beani and T. pingeli 

 Reinhardt . 



One may suppose that the common and numerous forms are subject to a 

 number of changes and morphological change to other types (whose ecology is 

 unknown) in different water masses. For example forms close to the typical 

 T. beani (an elongate body, long and sharp snout, etc.) are common in the 

 Pacific ocean, but close to them are some North Atlantic forms (no. 1932 Akad. 

 Nauk. from Greenland and T,. terraenovae Gilbert) . The typical T. pingeli is 

 common in the North Atlantic but is represented in the Bering Sea (T. pingeli 

 pacificus ). To some extent there are similar changes in the number of lateral 

 folds (if one compares T. metopiae Gilbert and Burke with T. omatistius Gilbert), 

 by having an increased number . 



In part the facts need not be explained on the basis of parallel evolution 

 or formation if it is presupposed that T. beani , as in the case of Icelus spatula 

 spatula Gilbert and Burke, occurs from Bering Straits to Hudson Bay and Greenland.^/ 



1/ 



In studying the Greenland type of Triglops we must consider Triglops pleurostictus 

 Cope, (1865) (usually placed in the synonmy of T. pingeli Reinhardt) and some 

 others described previously from the North Atlantic Ocean. 



2/ 



It is interesting to note that V. Vladykov (1933) showed that Triglops pingeli 

 pingeli occurs in Hudson Bay (on the basis of the caudal peduncle length in 

 the body, 2.6 -2.9%, instead of 3 . 3 - 4 . 4% for the Atlantic form) . 



18 



