456 Part III. — Twentieth Annual Report 



than broad, widest in the middle. The cephalo-thoracic segment scarcely 

 distinct, being indicated by a simple constriction ; thoracic segments all 

 coalescent. Abdomen very small, and apparently consisting of two 

 somites ; the first somite is short but moderately broad ; the second is also 

 short, and tapers abruptly to the slightly bilobed extremity. Caudal 

 furca extremely small. Ovisacs (two) large (fig. 8). 



The antennules are short, moderately slender, and five-jointed ; the first 

 and the last three are sub-equal in length, but the second is about one 

 and a half times the length of the third ; all the joints are sparingly 

 setiferous (fig. 9). 



The antennae are short and three jointed, the end joint is armed with 

 one small marginal and three or four stout terminal spines, which are 

 slightly hooked (fig. 10) ; they are not provided with secondary branches. 



The mandibles are large and elongated ; proximally they are some- 

 what dilated, but they taper gradually to the distal extremity, where they 

 are armed with two rows of short but stout tooth-spines as shown in the 

 drawing (fig. 11). No maxillae could be observed. 



The first and second maxillipeds are very stout but of a somewhat 

 rudimentary structure ; the terminal claws are very short, but stout and 

 tooth-like (figs. 12, 13). No thoracic feet were observed. 



Habitat. — Parasitic on specimens of a marine annelid, Eulalia viridis 

 (Ersted, dredged by the " Garland " in 55 to 65 fathoms in Loch Etive, 

 west coast of Scotland, on September 17th, 1901. Several specimens, 

 including old and young, were observed ; one or two of the specimens 

 occurred still adhering to fragments of the annelid, on which they 

 appeared to be able to take a very firm hold. 



At first I was not sure but that these Loch Etive specimens might 

 belong to the same species as those found by Professor M'Intosh on Nereis 

 cultrifera, Grube,* on the shores of the Channel Islands. I therefore 

 sent a specimen to him for his opinion as to whether it was the same as 

 those he had discovered ; in replying to me he pointed out certain differ- 

 ences observed by him, and also very kindly sent me an example of the 

 form from the Channel Islands so that I might more easily observe the 

 differences he referred to. He stated further that the form found by 

 him was the Nereicola ovata described by Keferstein in 1860.f I am 

 also indebted to Professor M'Intosh for the name of the annelid from Loch 

 Etive on which the copepods described here were obtained. 



The difference in the form of immature specimens of Nereicola concinna 

 from that of similar specimens of 2V. ovat is even more marked than in 

 the adults (fig. 14). 



HarpacticidtE. 

 Eucanuella spinifera, T. Scott. 



1901. Eucanuella spinifera, T. Scott, 19th Ann. Rept. Fishery 

 Board for Scotland., pt. iii., p. 245, pi. xviii., figs. 1-10. 



This species, described in Part iii. of the 19th Annual Eeport, has 

 again been observed in a gathering of bottom material collected to the 

 east of the Shetland Islands in 60 to 70 fathoms on May 22nd, 

 1901. Eucanuella is apparently a deep-water species. 



*On a Crustacean parasite of Nereis cultrifera, Grube, by W. C. Macintosh, M.D., 

 Micr. Journ., vol. x., N.S., p. 39, pi. v. 



fZeit. f. w. Zool., bd. xii. (1860), taf. xliii., f. 1-4, p. 461. 



