rgg] ALBATROSS EXPLOEATIONS. 601 



Several species of tli5 geuus SapMrina were taken, som?. of them veiy 

 brilliant in colors ; also manj^ small shrimp belonging \>o the Macrura* 

 and Schizopoda, and various species of Amphipoda and Isopoda. 



The Isopods are usually found clinging to floating sea- weeds {Sar gas- 

 sum and Fucus) or other floating objects, but are capable of swimming 

 about free. The most common species is Idotea robusta, which is a 

 particularly oceanic si^ecies, remarkable for its metallic luster and 

 bluish color. The commonest Amphipods are Themisto Mspinosa, which 

 often occur in vast numbers, both at the surface and in the trawl- wings,, 

 and CalUopius Iwviusculus, which is very common and often abundant 

 at the surface. There are also several species of Hyperia and allied 

 genera that live parasitic on jelly-fishes. 



The most interesting and beautiful Amphipod is a species of Phro- 

 nima (fig. 163). It is almost transparent and colorless, with the exception 

 of the black eyes. It is about an inch long and lives in a transparent, 

 gelatinous, tubular case or dwelling, which is open at both ends, and 

 usually about an inch in length and nearly as much in diameter. By 

 forcing a current of water through this tube it swims about with con- 

 siderable rapidity. Clusters of pinkish young ones are often seen 

 attached to the inside of the case. The curious structures or cases in- 

 habited by this species are not all alike, some being smooth and others- 

 longitudinally ribbed or keeled, the ribs having serrated edges. The 

 ribbed cases are evidently made from the posterior half of the test of 

 a large Salpa, common in the same waters, and having the same serrated 

 ribs. PerhaiJs the smooth ones are made from other species ot Salpa 

 and BoUolum. Among the surface Crustacea are delicate species of the 

 curious genus Lucifer {L. tyjpus f). Among the common small shrimp are 

 Latreutes ensi/erus, which is very abundant, and Leander tenuicornis, of 

 somewhat larger size. The Schizopod shrimp, Nyctiphanes Norvegica,*- 

 is often taken in the trawl- wings with several other related species. 

 Sometimes it is very abundant at the surface, especially northward. 



Two species of free-swimming oceanic crabs {N'autilograpsus minutus 

 and Neptunus Sayi) are of common occurrence, usually clinging to the- 

 clusters of floating sea-weeds, which they imitate in colors, but swim- 

 ming rapidly away when disturbed. The young of various crabs in 

 the zoea and megalops stages are taken in the surface nets, as well as 

 the curious larval forms of Falinurus, ^quilla, and allied genera. 



Several oceanic barnacles, esiieciallj Lepas peetinata and L./ascicularis^ 

 occur attached to floating drift-wood and other objects, and in one case 

 a small barnacle of this group occurred attached to a living siphono- 

 phorous jelly-fish (Porpita). Several oceanic annelida were taken, while 

 larval forms of annelids are not uncommon. Among the latter was a 

 very large larva, probably of Chcetopterus, but much larger than that of 

 the shore species. The larval forms of Echinoderms are not uncommon. 



* Prof. G. 0. Sars refers this species to a new genus (Nyctiphaves) recently estab- 

 lished by bim. It is the TJiysanopoda Norvegicfi Jf r«yer 



