Ke, aa ALBATROSS EXPLORATIONS. 591 
Several species of ths genus Saphirina were taken, some of them very 
brilliant in colors; also many small shrimp belonging vo the Macrura 
and Schizopoda, and various species of Amphipoda and Isopoda. 
The Isopods are usually found clinging to floating sea-weeds (Sargas- 
swum 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 species, remarkable for its metallic luster and 
bluish color. The commonest Amphipods are Themisto bispinosa, which 
often occur in vast numbers, both at the surface and in the trawl-wings, 
and Calliopius leviusculus, 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). Itis 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. Perhaps the smooth ones are made from other.species ot Salpa 
and Doliolum. Among the surface crustacea are delicate species of the 
curious genus Lucifer (I. typus?). Among the common small shrimp are 
Latreutes ensiferus, 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 (Nautilograpsus 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 zoéa and megalops stages are taken in the surface nets, as well as. 
the curious larval forms of Palinurus, Squilla, and allied genera. 
Several oceanic barnacles, especially Lepas pectinata and L. fascicularis, 
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 Chetopterus, but much larger than that of 
the shore species. The larval forms of Echinoderms are not uncommon. 

* Prof. G. O. Sars refers this species to a new genus (Nyctiphanes) recently estab- 
lished by him. It is the Thysanopoda Norvegice Sréyer 
