of the Fishery Board for Scotland. 



25 



Mollusc a. 



With the exception of one or two species of Cephalopoda, Mollusca- were 

 rarely met with, the only species of shell-fish observed being Fusus antiquus, 

 which occurred on one or two occasions ; the halibut did not apparently 

 take the whole shell, but simply snapped off the extended head as far as it 

 reached beyond the protecting shell. The operculum of one Fusus — a large 

 specimen — taken thus unawares, measures across the longest diameter 60 

 millimetres by about 33 millimetres at the widest part. But though shell- 

 fish were rare, Cephalopods were tolerably frequent, though sometimes the 

 brown horny jaws were all that was left to represent the cuttlefish — the soft 

 body having rapidly succumbed to the solvent action of the gastric fluid. In 

 several cases, however, fairly complete specimens were obtained, showing 

 that the cuttlefish had been swallowed whole, the body first, with the tentacles 

 streaming behind, as was apparent from the position of the organism in the 

 stomach. The cuttlefishes observed belonged to three, or perhaps four genera, 

 viz., Loligo, Eledone (and probably Octopus), and Ommatostreplies. The 

 ELedone and Octopus are Octopods — that is, they are provided with eight 

 tentacles; they differ in the Eledone having tentacles with a single row of 

 suckers and the Octopus with a double row — the suckers of the one row 

 alternating with those of the other. This, which is one of the more obvious 

 differences between the two, is in the case of a partly digested specimen 

 somewhat difficult to make out. The specimens, however, which were 

 sufficiently perfect for identification were found to be Eledones — probably 

 Eledone cirrcosa. Several specimens of Loligo were observed, but with the 

 exception of perhaps one or two, they all belonged to Loligo vulgaris 

 (Lamarck). None of them appeared to be full grown, and the shell (or bone) 

 of the largest specimen measured only 7g inches (about 20 centimetres) in 

 length, and 1| inches (3*5 centimetres) in width at the widest part. The 

 shell of a smaller specimen was rather narrower in proportion to the length ; 

 this one measured fully 4| inches (110 mm.) by g of an inch (16 mm.) 

 in width. Ommatostrephes was represented by a piece of the anterior end 

 of the shell (or bone) of a specimen of moderate size. 



The Echinodermata. 



The Echinodermata were only sparingly represented by fragments of 

 Spatangus and a nearly complete but crushed specimen of Cidaris papillata. 

 The discs and arms of a few Ophiurids were also observed, but these were 

 probably derived from the stomachs of Gadoids which the halibut had 

 swallowed. 



The Anneltds. 



Traces of Annelids (Ohcetopods) were observed in a few stomachs, but 

 these, like the Ophiurids mentioned above, may have come from the stomach 

 of a fish swallowed by the halibut. 



Table shewing Number of Fishes Examined. 



The following is a tabulated summary of the total number of stomachs 

 examined each month, the number containing food that could be identified, 

 and the number empty, or the contents of which could not be determined : — 



[Table, 



