SEA-FISHEKIES LABORATORY. 153 



Habitat, obtained from the mud collected on the 

 Mussel beds between Morecambe and Heysham ; only a 

 few specimens were obtained. 



Remarks. — This species is very distinct from Idya fur- 

 cata and also from two other species recently described — 

 Idya longicornis, T. and A. Scott, and Idya gracilis, T. 

 Scott — -and can easily be recognised from either of them 

 by the elongate form of the animal, the short antennules 

 and the small fifth feet. 



Idya gracilis, T. Scott. 



[T. Scott, Thirteenth An. Kep. Fish. Board for Scot., 

 pt. III., p. 171, 1895.] 



A number of specimens of this species were obtained 

 from the shelly material dredged 1 mile off Spanish Head, 

 Isle of Man, from a depth of 16 fathoms ; it is easily 

 recognised by the long and slender inner branches of the 

 first pair of swimming feet and also by the shape and 

 arrangement of the setse on the fifth pair of feet. 



Family SAPPHLRiNiDiE, Thorell. 



Modiolicola insignis, Aurivillius. 



Living as a messmate within the mantle of the " horse 

 mussel," Mytilus modiolus. A number of specimens 

 were found in the examples of this Mollusc which were 

 brought up in the trawl-net of the steamer, while working 

 in the vicinity of the north end of " the Hole " on March 

 23rd, 1895. This appears to be a widely distributed 

 species of Copepod, its range being probably co-extensive 

 with that of the Mollusc. It has been recorded from the 

 Firth of Forth, the Moray Firth, and from the vicinity of 

 Mull. It has also been obtained in specimens of the 

 same species of Mollusc dredged by Dr. Norman in 1893, 

 off Trondhjem in Norway. 



