603 



cular joints comlnned. Anterior gnathopoda with the propodos about the 

 length of the carpus and considerably expanded in the middle, palm about 

 the length of the hind margin. Posterior gnathopoda in female with the 

 carpal lobe long and narrow, armed at the end with several recurved den- 

 ticles in addition to the bristles, propodos rather large and expanded, with the 

 palm longer than the hind margin; posterior gnathopoda in male extremely 

 powerful, carpus very massive and having the thumb-like process comparatively 

 large and somewhat curved, with a well-marked triangular expansion of the upper 

 edge, propodos nearly as long as the carpus but considerably narrower, and 

 somewhat curved, with the lower edge slightly concave in the middle, dacty- 

 lus ver3' large, lamellarly falciform. Basal joint of the 2 anterior pairs of 

 ])ereiopoda very broad, with the anterior edge boldly curved; the 3 posterior 

 pairs moderately slender. Penultimate pair of uropoda with the rami subla- 

 mellar and densely edged with small spinules; last pair with the basal joint 

 rather large and broad at the base, terminal joint not attaining to half its 

 length, and minutely bidentate at the tip. Telson twice as broad as it is 

 long, and transversely truncated at the tip. Body of a pale orange hue, and 

 mottled with reddish brown pigmentary spots, antennse banded with chestnut- 

 brown. Length of adult female 6 mm., of male 7 mm. 



RcmarJis. — This form was first described by Templeton as Cerajms 

 (ihdilns, and the male sxibsequently recorded by Sp. Bate under the same 

 name, whereas the female is described by that author as Dercothoi' punctata. 

 It may be best distinguished from the other species of the genus by the 

 structure of the posterior gnathopoda in the male, the carpal process of which 

 is very lai'ge and conspicuously bidentate. 



Occurrence. — The species occurs not infrequently off the south and 

 west coasts of Norway in depths varying from 10 to 41 > fatlioras, especially 

 on rocky bottom overgrown with red algge and Hydroidae. It constructs for 

 itself tubes of muddy substance, which are affixed, sometimes in great num- 

 ber, to stems of Hydroidte or algse. 



BhtriJintion. — British Isles (Sp. Bate), Boliaslan (Bruzelius), Kattegat 

 (Meinert), coast of France (Chevreux), Adriatic (Heller), Gulf of Naples (Costa,), 

 Azores (Barrois). 



