284 



ill form, its tip jutting out above the insertion of tlie dactylus as a triangu- 

 larly pointed projection setous at the edge, palm somewhat curved, and de- 

 fined below l>y a very sliglit obtuse angle, its edge mimitely serrulated 

 throughout; propodos of male still larger than in female, and more dilated in 

 its proximal part to receive the powerful muscles moving the dactylus. Pe- 

 reiopoda nearly equal in size, and provided with very short marginal spi- 

 nules, dactylus in all very small, basal joint of last ])air oval, posterior edge 

 serrated, and strongly curved in tlie middle. Last pair of uropoda with the 

 rami much shorter than the basal part. Telson very elongated, about 3 times 

 as long as it is broad at the base, and gradually tapering to an acuminate 

 point. Body of a pale flesh-colour, with slight transverse bands of a somewhat 

 darker hue, ova in the marsupial pouch of a fine grass green colour. Length 

 of adult female reaching 14mm, that of male 15mm. 



l!ciuor/,'s. — By the peculiar structure of the gnathopoda this form 

 is so highly characterised as to be at once recognized from most other Am- 

 phipoda. Also from the following species it may readily be distinguished, by 

 several well-marked characteristics. Of the exotic species the L. Alicrsi of 

 Stebbing is that which comes nearest to the present form. 



Occurrence. — Off the soiith and west coasts of Norway this species is 

 far from being rare, occurring even in some places, as in the Trondhjemsfjoi'd, 

 in great abundance. It is found in depths varying from 30 to 150 fathoms, 

 now free, now semiparasitic in the branchial cavity of Ascidiae. 



Bisirilmtion. — British Isles (Montagu and others), Kattegat (Meinert), 

 coast of France (Chevreux), Mediterranean (Costa), Azores (Barrois), Green- 

 land (Hansenj. 



2. Leucothoe Lilljeborgii, Boeck. 



(PI. 101, lig. 2). 



Leucoihoii LiUjeborgU, Boeck, Forhaixll. .Skand. Nalnrf. Silc Mode 1860. 

 Syn: Leucothoe articulosa, Lilljeb. (non Mont . 



» Leucothoe furina, Norman & G. O Sars (non Savigny). 

 » Leucothoe injparicornis, Norman 



Body even somewhat more slender than in the type species, and less 

 tumid. Cephalon nearly twice as long as the 1st segment of mesosome, fron- 

 tal projection somewhat more produced than in L. ,syinicarpa, lateral corners 

 evenly rounded. First pair of coxal plates narrowly rounded at the anterior 

 corners, 4th jiair pentagonal in form, anterior corners produced to an acute 

 point. Last pair of epimeral plates of metasome forming at the lateral cor- 

 ners a strong, recurved, acuminate projection defined above by a deep sinus, 

 posterior edge strongly arcuate. Eyes rounded triangular in form, pigment 



