ON MYSIS. 29 



ing at times to black, having invariably the greater part 

 of the anterior scales, inner branch of the superior 

 antennee and joints of the outer laminae of the tail, black, 

 and the fringe of the scales tinged with pink ; lower down, 

 amongst the littoral Fuci, it takes various tints of brown, 

 and those obtained from sites abounding in Zostera and 

 Ulvse, present us with green colours of greater or less 

 intensity. 



This species has been occasionally met with in the 

 stomachs of Herrings, but has never been observed like 

 the other species in any great numbers together, but scat- 

 tered and solitary, often associated with M. vulgaris. 

 They are extremely quick sighted and wary, darting away 

 or descending tail foremost or retrograde, when any 

 attempt is made to capture them, and more frequently 

 swim with the body in a perpendicular direction, than in 

 any other. In the Lee, they do not appear until towards 

 the latter end of June, but remain until the approach of 

 winter. Length 1| inch. That this is the species indi- 

 cated by Montagu, under the title of Cancer Astacus 

 multipes, can hardly be doubted from the sketches given 

 of it in Linn. Trans. Vol. IX. t. 4, fig. 3, and the accom- 

 panying description, derived from specimens occasionally 

 found dead amongst Shrimps taken at Salcom)), and in the 

 Kingsbridge estuary : it appears also from the same 

 authority, to have been noticed on the coast of Kent, by 

 Mr. Henry Boys of Sandwich. The figure given by Herbst 

 in his Work on Crabs, &c. for Cancer flexuosus Plate 

 XXXIV. fig. 8, natural size, and I, magnified, described 

 Vol.11. p. 114, appears also referable to the present species, 

 although like many of the figures in that valuable work, 

 faulty in the colouring ; as with us, he describes it — as 

 existing thinly scattered in the Baltic. 



The remabiing species have the middle lamina of the 

 tail entii'e. 



