67 



Male somewhat smaller than female, but otherwise of a very similar 

 external appearance. Anterior antennse, as usual, prehensile. Appenclicular lappet 

 of genital segment replaced by a small trisetose piece. 



Body in both sexes tinged all over with a rich carmine. 



Length of adult female 1.05 mm. 



Remarks. This is an easily recognizable form, being distinguished from 

 all our other Copepoda both by its general appearance and the beautiful colour 

 of the body. The Oniscidium armatum of Glaus seems to be identical with the 

 present species. 



Occurrence. I have met with this form in several places on the west coast 

 of Norway, as also in the Trondhjem Fjord, in depths varying from 6 to 20 

 fathoms, sandy bottom. It is at once observable, even with the naked eye, owing 

 to its unusual colour. 



Distribution. Scottish coast (Scott), Mediterranean (Philippi). 



Fam. 7. Tegastidae. 



Characters. Body short and compact, highly compressed, with very hard 

 integuments. Cephalic segment large, in some cases with a chitinous stripe across 

 the back, indicating the posterior limit of the head; lateral parts very deep and 

 terminating behind in a triangular promontory; rostrum short, deflexed, not de- 

 fined at the base. Epimeral parts of the 3 succeeding segments rudimentary. 

 Last segment of metasome more or less completely coalesced with the genital 

 segment, which more generally forms a large and highly chitinized dilatation 

 below, armed with variously formed projections. Distal part of urosome, as a 

 rule, very small and thin-skinned. Caudal rami short, with the normal number 

 of setae. Eye well-developed, trilobate. Anterior antennae slender, 6 8-articulate, 

 and but sparsely setiferous; those in male transformed in the usual manner. 

 Posterior antennae 3-articulate, with a very small outer ramus; terminal joint 

 wanting the usual geniculate setae. Oral parts, except the posterior maxillipeds 

 very small; the latter well developed, terminating in a strongly clawed hand. 

 First pair of legs imperfectly prehensile, both rami short, uniarticulate. Natatory 

 legs with the rami extremely slender, the inner one being the longer. Last pair 

 of legs of different shape in the two sexes, proximal joint in female greatly ex- 

 panded, in male simple. 



