ami if Dcrwetitwatcr and H .ssenlhic litH Lalce.<>. 181 



10-12 (III-IV 7-8), its origin nearly equidistant from tip of 

 snout and base of caudal ; longest ray from J to as long as 

 the head. Anal 1:5-15 (III- IV 9-12). Pectoral extendin;,- 

 §— I of the distance from its base to the base of ventral ; ven- 

 trals ori<;inatinf; below or a little behind the origin of dorsal, 

 extending ;.'-$ of the distance from their base to the origin of 

 anal. Caudal forked. Least depth of caudal peduncle ^ or 

 a little more than V' the length of head, nearly e(|ual to or 

 even a little greater than the distance from the base of the 

 last anal ray to the first procurrent caudal ray. Bluish or 

 olivaceous above, silvery on the sides and btdow; fins 

 yelKiwish or grevish. 



Castle Loch and Mill Loch, Lochmaben, Dumfriesshire. 



The description is based on fourteen examples, measuring 

 from loU-lDO mm. in total length. 



Coregonus gracilior, sp. n. (PI. VIL) 



Depth of body ^4— 4^ in the length, length of head •4?-4i. 

 Snout a little shorter than eye, the diameter of whicli is 3^— H^ 

 in the lengtii of head and equal to the interorbital width. 

 Piseniaxillaries continuing the line of the upper profile of the 

 snout ; maxillary ^ or slightly more than \ the length of 

 head, extending to below anteiior ^ of eye; lower jaw 

 projecting. 25—28 gill-rakers on the lower part of the ante- 

 rior arch, the longest nearly equal to the diameter of eye. 

 Scales G7-70 y'j^, 6 or 7 between lateral line and root of 

 ventral fin, 18-21 round the caudal peduncle. Dorsal 12-14 

 (IJI-IV 8-10), its origin equidistant from tip of snout and 

 base of caudal or a little nearer the tbrmer ; longest ray ^ the 

 length of head or a little less. Anal 14 (IV 10). Pectoral 

 extending |-;^ of the distance from its base to the base of 

 ventral ; ventrals originating below or a little behind the 

 origin of dorsal, extending i-'^ of the distance from their 

 base to the origin of anal. Caudal forked. Least depth of 

 caudal peduncle f-? the length of head and less than the 

 distance from the base of the last anal ray to the first pro- 

 current caudal ray. Bluish or olivaceous above, silvery on 

 the sides and below ; fins j)ale yellow. 



Derwentwater and Basscnthwaite Lakes, Cumberland. 



The description is baised on five exani|)l<s from Derwent- 

 water, measuring from 160-100 mm. in total length. 



This S[)eiies is seen to differ from C. vandebius, when 

 specimens of the same size are compared, in the more elon- 

 gate body and Uiore slender caudal peduncle, smaller head, 

 shorter paired and lower unpaired fins, whilst the dorsal fin 



