674 Prbto peddtus. 



which might justify their separation. In the present state of our know- 

 ledge, however, of this curious animal, it will be safer to regard these dif- 

 ferences as the mere variations of the same species. 



Variety 1. — Hands oval with a single denticle at the base : head rounded 

 in front: branchial lamellae larger and elliptical. Obs. To this variety 

 the figures of Miiller and Montagu belong. 



Variety 2. — Anterior hands triangular, somewhat lobed at the base ; the 

 wrist deeply sinuate : posterior hands oval, with two teeth at the base, 

 and serrulate on the inner aspect : head very obtuse in front : branchial 



Prbto pedatus, var. 2. 



lamellae smaller and cylindrical. Obs. All the specimens I have seen 

 belong to this variety. 



Latreille (Cuvier, Regne Animal, torn. iv. p. 127.) and Desmarest assert 

 that the figures of Miiller and Montagu refer to distinct animals, which do 

 not even pertain to the same genus. There is some error in this ; for the 

 figures are in reality more closely alike than could have been anticipated, 

 when it is remembered that they are both original, and taken by different 

 draughtsmen ; and they unquestionably represent the same species. 



The above, so far as I am aware, are all the laemodipodans 

 which have been ascertained to inhabit the British seas. 

 Berwick upon Tweed. 



[Corrections by Dr. Johnston to certain of his Illustrations 

 published in this Magazine.] — At the conclusion of this vo- 

 lume, I take the opportunity of making the following corri- 

 genda to my Illustrations in British Zoology : — 



1. Plandria cornuta. (V. 344.) — At p. 429. of the same 

 volume this is considered synonymous with P. vittata of Mon- 

 tagu ; but this is an error, for the two species are quite dis- 

 tinct. 



2. Carinella trilinedta. (VI. 232.) — This is the Gordius 

 annulatus of Montagu, in Lin. Trans., vii. 74. 



3. Sigdlion Boa. (VI. 323.) — This is distinct from any 

 of the species described by Audouin and M. Edwards. The 



. 



