498 Part III. — Twentieth Anniial Report 



tion of them were either empty or filled with a watery fluid of about the 

 same specific gravity as ordinary sea water. The fact that the stomachs 

 of these fishes are found so frequently containing more or less of this 

 watery fluid, and having sometimes mixed up with it a comminuted and 

 whitish-coloured matter, has given rise to curious conjectures concerning 

 the food supply of these fishes. P. -J. van Beneden in his work on 

 Animal Parasites remarks that " Fishermen affirm, and the examination 

 of the animal's stomach confirms their assertion, that the Cyclopterus 

 himpus feeds on nothing but the excreta of other fishes."* It is probably 

 for this reason that he calls the Lumpsuckers " crotophagous fishes." t 

 Occasionally I have found the stomachs of Lumpsuckers well filled with 

 small Coelenterates, such as PJeurohrachia or Beroe, and perhaps the 

 occurrence of the comminuted bodies of such organisms may, partly at 

 least, account for this opinion. 



The Lumpsuckers referred to here were all, with the exception of 

 two small specimens from Annan, captured in the Bay of Nigg, near 

 Aberdeen, in the nets of the salmon fishers. It would appear that the 

 Lumpsuckers com.e into the Bay to spawm, and the specimens captured in 

 the salmon-nets, and which I examined, were therefore for the most part 

 adult forms. The length of the two small specimens sent from Annan 

 (Solway Firth), and which were collected on April 30th, 1900, 

 measured 4'2 and 4 '5 centimetres respectively ; the only food found in the 

 stomachs of these specimens consisted entirely of remains of Gammarus 

 locusta. The Lumpsuckers from the Bay of Nigg, which numbered one 

 hundred and forty-four, were all, with the exception of eleven, collected 

 during the present year (1901). The eleven referred to were captured 

 between the 16th and 18th of May, 1900, and are included here because 

 the stomachs of a few of them contained a considerable number of Cope- 

 poda, chiefly Temora longicornis, whilst among other things observed 

 were Centropages Jiamatus, Gammarus locusta, and Llothea haltica. In 

 the stomachs of five specimens collected in the salmon-nets in February no 

 solid food was found nor anything that could be identified ; but in the 

 stomachs and intestines of four of the specimens a considerable quantity 

 of watery fluid was observed ; young cestoid parasites were frequent, 

 especially in their intestines, but the fish were apparently in a healthy 

 condition, Forty Lumpsuckers were examined during March ; the 

 stomachs of seven, taken on the 9th of the month, were all more or less 

 filled with watery fluid, nothing that could be identified being noticed. 

 The stomachs of two captured on the 13th contained a quantity of matter 

 closely resembling Fleurohrachia or some similar Coelenterate, but was 

 not sufficiently perfect for identification. Five captured between the 

 14th and 15th had their stomachs more or less full of fluid. On the 19th 

 thirteen specimens, comprising ten males and three females, were captured ; 

 and in the stomachs of four of the males \vere found the remains of 

 Amphipods and Isopods, the following species being distinguished, viz. : — 

 Hyperia galha, Calliopkcs heimisculus, Gammams loaista, and Idothea 

 emarginata ; the contents of the other stomachs consisted only of a little 

 semi-fluid matter. Seven specimens were captured between the 21st and 

 22nd, but only in the stomachs of two was there anything that could be 

 identified. One of these contained the remains of Pandalus montagui, 

 and the other the remains of Gavunarus locusta ; the other stomachs con- 

 tained the usual watery fluid. Of. the five specimens captured on the 

 27th, two contained watery fluid, two were empty and greatly distended 

 with air, while in one the remains of a chaetopod Annelid and a specimen 

 of Hyperia galba were observed. 



* Animal Pai-asi(es, The International Scientific Series, vol. xx., p. 79 (1876). 

 f Les Poissons des Cotes de Belgifjve. 



