229 



Exemplar von 27 cm. Länge, ganz wie Richardson es von seiner 

 Art angiebt, in der ersten Rückenflosse 7 Stacheln und in der 

 zweiten 13 Strahlen hat. Indessen variirt diese Zahl, indem die 

 beiden andern Exemplare D. 8 — 14 zeigen, ebenso wie alle drei 

 in der Strahlenzahl der Analflosse von einander abweichen, da 

 dieselbe bei dem grössten Exemplare 14, und bei den andern 

 beiden 13 und 15 beträgt.» 



Professor Lütken again brought up the question in the 

 first part of his meritorious «Korte Ridrag til nordisk Ichthyo- 

 graphi» ^). C. hexacornis Rich, from the arctic America he 

 considers to be no other than С quadricornis L., and after 

 having examined one of the specimens from the Germania- 

 expedition and having compared it with specimens of C. qua- 

 dricornis from the Raltic, he could find no difference except 

 that the front of the East-Greenland Fourhorned Riillhead is 

 more concave than the front of the Raltic one^), but this 

 difference L. does not consider to be of any great importance: 

 «C. hexacornis Peters» from East-Greenland is the very same 

 species as the genuine C. quadricornis L. 



The abundant material brought home by the Amdrup- 

 expedition invites us to a renewed comparison. I have there- 

 fore taken a series of measurements of the 16 specimens at 

 hand together with 6 specimens in our Museum from the Baltic 

 (and the lake Vettern)^). 



From these measurements we see that the head in the 

 Raltic form is comparatively a little larger and 

 has longer jaws. The length of the head amounts indeed 



Foreløbige Meddelelser om nordiske ulkefiske. Vidensk. Medd. Naturhist. 



Foren. Kbhvn. 1876 (p. 37.5). 



Jordan and Ever mann have been so unfortunate as to quote Liitken's 



words in such a manner that the fact is reversed (Fishes of North and 



Middle America II, 1898, p. 2001). 



Vettern, 1 specim. (138 mm.); «Central-Sweden» 2 specim. ($ 178 mm.; 



d" 246 mm.) ; the gulf of Bothnia, 2 specim. (d" 208 mm., 9 242 mm.) ; 



the Baltic by Stockholm ($ 230 mm.). 



