681 



are attached 3 slender bristles. Colour 'somewliat varying, now more or less 

 d-Ark reddish brown, now greenish, but generally exhibiting along the back a 

 series of light ijatches, one in each segment. Length of adult female reach- 

 ing 18 mm, of male 20 mm. 



Bemarks. — Thei'e cannot, I think, be any doixbt, that the A. podo- 

 ccroides of Rathke is the same species as that described many years pre- 

 viously by Montagu as Cancer (gammarus) rnhricains, and subsequently 

 recorded by British authors as Amphitho'e nibricata. Kroyer described the same 

 species under another name, viz., A. alhomaculata, and the A. littorina of Sp. 

 Bate is nothing less than an adult male of this species. The colour is ratber 

 variable, according to the localitv', and although I have never met with 

 specimens of that brillant crimson, described b)' British authors, it is not 

 unusual to find it of a deep reddish In'own colour. Most generally however it 

 exhibits a lighter, more or less greenish hue, the bod\'- being mottled all over 

 with very small dark pigmentary spots. 



Occurrence. — The species is very fre(|uently found along the whole 

 coast of Norway, from the ChrLstianiafjord to Vadsa, in comparativelj' shallow 

 water, among algse. According to Sp. Bate, it constructs itself a kind of 

 nest, composed of different foreign matters spun together by fine fibres. 



DistriltHtion. — British Isles (Sp. Bate\ Bohuslan (Bruzelius), Kattgat 

 (Meinert), Heligoland (Meinert), coast of France (Chevreux), Azores (Barrois). 



Gen. 2. PleonexeS, Sp. Bate, 1857. 



Syn. : Amphithoii, Sp. Bate (part). 

 » Sunamphithoe, Sp. Bate (part). 



Body less slender than in the preceding genus, otherwise of a \ery 

 similar appearance. Coxal plates of middle size, iith pair with the anterior 

 lolic riiuiidcd at tlie tip. E\'es small. Antennte comparatively strongly built, 

 witli the articulations of tlie flagella rather thick and very sharply defined, 

 the superior ones shorter than the inferior, and without any accessory appen- 

 dage. Mandibular palps very narrow, witli the terminal joint linear, and 

 setiferous at the tip only. Posterior lip with the lateral lobes not bifid at 

 the tip. Palp of 1st pair of maxilla? liaving the terminal joint long and 

 naiTow. Oral parts otherwise resembling those in AmphithoV. (rnatliopoda 

 comparatively stronger than in that genus, and rather unequal, the posterior 



77 — Crustacea. 



