190 Part III. — Twenty-second Annual Beport 



They are to be found in Aberdeen Bay in October and November, 

 and, as above stated, an odd specimen may be procured even in January. 

 The size of those obtained ranged from 12 to 40mm. (1-1 1 inches), 

 transformation being completed and bottom-life begun as a rule about the 

 latter size. In the Dornoch Firth a few were also obtained in October 

 and November, from 22 to 38mm. In the Clyde, in the deep water 

 across the mouth of the Firth, in June and July, a number were procured 

 ranging from 6*5 to 37mm., the smaller forms being generally caught 

 towards the surface and the larger forms deeper. On 1st August these 

 measured 14, 15, and 17mm. I am indebted to Dr. Williamson for 

 particulars of these. 



In the absence of a complete periodic series of tow-net collections 

 extending over the whole time from the beginning of spawning, it is not 

 possible to tell the age of the specimens given in the Table ; but if spawn- 

 ing ceases in August it follows that those got in Aberdeen Bay in October 

 and November must be two months old, and may be more, and that the 

 specimen, incompletely metamorphosed, procured on 15th January, was 

 over four months old. The size at which metamorphosis is completed, 

 and therefore the duration of the pelagic stage in this species, is there- 

 fore considerable. 



The young forms living on the bottom were also sometimes caught in 

 the small-meshed net, enveloping the cod-end of the otter-trawl, or in 

 the shrimp-trawl. Thus, on 24th October, in sixty fathoms some miles of! 

 Aberdeen, nine specimens were taken, five of which measured 42mm., and 

 one each 37, 38, 40, and 43mm. These clearly belonged to the preceding 

 spawning season, and would be a few months old. On 28th December, 

 in thirty fathoms, off Burghead Bay in the Moray Firth, fourteen specimens 

 were secured which measured as follows: — 



Mm. 



All these also belonged to the previous spawning season ; the next 

 largest got in the net was 137mm. {see below). 



In the same locality, on 14th November, one measuring 56mm. 

 (2j^^ inches) was taken, and it belongs to tho same category. On 21st 

 January, in fifty fathoms, in the Moray Firth, a specimen of 47mm. was 

 taken ; on 23rd January, in the same place, another of 45mm., the tail of 

 which wus, however, damaged, and its real length would be several milli- 

 metres greater. On 1st April, oflf Burghead Bay, in thirty-two fathoms, 

 seven small witches were caught of the following sizes : — 60, 65, 66, 74, 

 76, 77, 83mm. (2|-3J inches), which would be, approximately, from 

 eight to ten months old ; the next largest was 144mm. 



On the west coast, two were caught in Loch Long, off Ruad Dubh, in 

 thirty-five fathoms, on 20th September, which measured 57 and 58mm. 

 respectively; on 17th September, in Upper Loch Etive, in fifty-two 

 fathoms, six were taken, four of which measured 47ram., one 57 mm., 

 and one 60 mm.; on 21st April, one measuring 90mm. (3| inches) 

 was obtained seventeen miles off Corsewall Point. There seems little 

 doubt that all these also belonged to the spawning-season immediately 

 preceding. 



Holt, on the coast of Ireland, caught specimens of 42mm. in eighty 

 fathoms on 19th August, which he was of opinion were from eggs 

 spawned early in the season, and were thus from four to six months old ; 

 and in July he got one in one hundred and forty-four fathoms, measur- 

 ing 12.5cm., which he believed to be about one year or more old.* 



In some of the hauls a number of specimens were procured belonging 

 to a fairly well-defined older group, and these, with some others, are 

 represented in the accompanying Table. 



» Sci Trans. Roy. Dithlin Soc. V (Ser. II.) 85 



