— 63 — JOHS. SCHMIDT 



whiting fry in ISO? may possibly therefore lie in this peculiarity in the occurrence of the 

 whiting '. That the small whiting fry may occur in considerable quantities in the western 

 part of the Channel has indeed been proved, as shown above, by our hauls, and the same 

 fact is illustrated by the contents of some pelagic hauls made by the Plymouth Laboratory 

 in May and June 1906 and kindly sent me for determination by Dr. E. J. Allen. One of 

 these hauls made in Plymouth Sound on May 22nd, 1906, contains for example, over 300 

 whiting fry of '/s — 1 cm. in length, which is a very considerable number in a haul of half 

 an hour. 



Altogether, the data show that the whiting reproduces in large numbers in 

 the Channel, where the pelagic fry occur in abundance in the spring and 

 summer months, at lea'st in the western parts. 



6. Bay of Biscay 

 Our observations in the first half of May 1906 show that the pelagic whiting young 

 were present in the most northerly parts of the Bay, although in small quantities. The 

 length of these fry was about P/s cm. We did not find any pelagic whiting fry in the 

 most southerly parts of the Bay. From this we may conclude that there can be no 

 question of a spawning of the whiting on a large scale in the southerly parts of the Bay 

 of Biscay, but it is quite probable that the pelagic fry would have been found, at least 

 somewhat further to the south, if we had worked nearer to the coast of France than we 

 did. I must therefore be content with stating, that Gadus merlangus reproduces in 

 the most northern parts of the Bay of Biscay in the neighbourhood of the 

 French coast but apparently not in the southern part of the Bay. This appears to 

 agree very well with the information kindly given me by Dr. A. Cligny of Boulogne-sur- 

 Mer in a letter: "Le G. merlangus est très abondant dans la Manche, surtout dans la 

 Manche orientale, devient de plus en plus rare vers l'ouest et très rare sur la côte sud de 

 Bretagne". 



7. Gadus Esmarki, Nilsson, Norway Pout (Chart V) 



§ 1. Remarks on the identification 



The pelagic fry of Gaäus Esmarki may often resemble the corresponding stages of 

 Gadus wimdus, so that it has been impossible from external characters alone to separate 

 them. In the beginning I only knew the two species respectively from Iceland and the 

 Channel, and from these widely separated regions the species showed such great differences 

 in external characters (size of the eyes, shape of the body, development of the fins etc.), 

 that the types could be characterised by these, as indeed 1 have already shown (Gadus, 

 Part I and II). Later however (1905 and 1906), the fry of the two species were found 

 together in quantities in the same hauls on the west of the British Isles and it appeared 

 often very difficult, indeed quite impossible, to separate them from the external characters 

 alone. It has proved fortunately that in the number of vertebrae, which can be 

 counted in not too small specimens after clearing in xylol or the like, we have a certain 

 method of distinguishing the two species. 



> According to Dr. A. Clignt the wliiting is very common in the Channel; see under the Bay of 

 Biscay. 



