of the 'Fishery Board for Scotland. 



109 



IL— ON SOME NEW AND RARE CRUSTACEA COLLECTED AT 

 VARIOUS TIMES IN CONNECTION WITH THE INVESTL 

 CATIONS OF THE FISHERY BOARD FOR SCOTLAND. 



By Thomas Scott, LL.D., F.L.S., Mem. Zool. Soc. de France. 

 (Plates II.-YI.) 



Though the larger, or, as they are sometimes called, the higher 

 Crustacea of the British seas are now fairly well known, our knowledge 

 of the smaller forms is still very defective ; and as these smaller species 

 constitute an important part of the food of small and young fishes, their 

 study becomes important from a fisheries' point of view as well as from 

 the point of view of the naturalist. 



A large number of gatherings of small crustaceans has been examined 

 during the past year. These gatherings have been collected at various 

 times, and some of them several years ago ; some of the earlier gather- 

 ings were not examined or only partially examined at the time they 

 were collected, as other work requiring more immediate attention had to 

 be done. The re-examination of these collections has yielded several new 

 forms, besides a number of rare and interesting species already described. 

 The new species all belong to the Copepoda — a group which from their 

 great abundance, their wide distribution in all our seas and estuaries, and 

 their nutritive qualities, is of immense value as food for fishes. 



In a recent paper on the food of fishes* it is shown that the young of 

 almost all the food-fishes live very largely on small crustaceans, and a 

 considerable proportion of them belong to the Copepoda. 



Among the species recorded in the present paper the following appear 

 to be undescribed : — 



Ameira jpusilla^ T. Scott (sp. nov.). 



„ amhigua, T. Scott (sp. nov.). 

 Delavalia minutissima, T. Scott, (sp, nov.). 

 Tetragoniceps pygmcBus, T. Scott (sp. nov.). 

 LaopTionte gracilis^ T. Scott (sp. nov.). 

 Cletodes negleda, T. Scott (sp. nov.). 

 Enhydrosoma gracile, T. Scott (sp. nov.). 

 Enhydrosoma minutum, T. Scott (sp. nov.). 

 Dactylopus Utf oralis, T. Scott (sp. nov.). 

 Dactylopus vararensis, T. Scott (sp. nov.). 

 Dactylopus mixtus, T. Scott (sp. nov.). 

 Paranthessius dubius, T. Scott (gen. et sp. nov.). 



While among the other species recorded in the sequel there are severa . 

 that are of special interest. For example, Parastephos pallidus (G. O. 

 Sars) is a copepod new to the British fauna. 



Eucalanus crassus, Giesbrecht, is a copepod which was added to the 

 British fauna a few years ago, and is now recorded from a new station. 



Stephos scotti, G. 0. Sars, is also recorded from a new station, and the 

 male is described for the first time from Scottish specimens. 



* Twentieth Annual Report Fishery Board for Scotland, Part III., pp. 486-538 (1902). 



