[91] ALBAtROSS EXPLORATIONS. 59^ 



The various pieces of drift timber found floating in the Gulf Stream 

 have always been found tilled with the burrows of a large species of 

 Teredo {T. megotara, fig. 127), which seems to be the only common species 

 in that region. 



Among the most abundant forms of pelagic life are several species of 

 Salpa. One of these is the common species of the New England coast 

 {Salpa Caboti, figs. 147, a), which grows to be only about an inch long, in 

 the solitary form, but it often occurs in vast quantities, completely filling 

 the sea, so that surface nets are quickly filled and clogged up with it. 

 In this there are delicate reticulations of clear blue lines on the edges of 

 the mantle, gills, and other internal organs, and the nucleus is usually 

 deeply tinged with blue. 



A much larger species, which is also very abundant on most trips, 

 often grows in the solitary form to the length of 3 to 4 inches or more, 

 with a diameter of 1 to 1.25 inches, while the chained individuals are 

 sometimes even longer, with each end running outinto a long, tapering, 

 acute tip, while both ends are abruptly terminated in the solitary in- 

 dividuals. The body has eight longitudinal angles or keels, serrated 

 along their edges. The chains often become several feet long, but easily 

 break up when disturbed. This species (figs. 148-150) is related to S. 

 maxima Forskal, but is apparently distinct. It is, however, probably 

 identical with S. clostra, M. Edwards, of the Mediterranean, well figured 

 in the illustrated edition of Cu\aer (Plate 121, figs. 2-2d). 



In this the whole body is nearly colorless, except the nucleus, 

 which is dull orange or orange-brown, but whitish on the sides. On 

 many occasions a bushel or more of this species has been caught in the 

 trawl, evidently from near the surface. In the summer of 1884, this 

 species was taken in Vineyard Sound and Buzzard's Bay, August 25 

 to September 5, in considerable numbers, but not so large as those found 

 in the Gulf Stream. This must be an unusual occurrence, however. A 

 special collection of this species was made in 1882, by hardening in 

 chromic acid, to be used by Professor Brooks for making sections in 

 studying its anatomy and embryology, and were found by him very sat- 

 isfactory. 



Another very interesting species {8.pinnata),-pTevio\ialy known from 

 t^e Mediterranean, was taken in 1883, off Cape Hatteras. In this species 

 the chained individuals are united together in such a way as to form 

 circular or wreath-like groups. Species of Doliolum (fig. 146) and of 

 Appendicularia were also taken, but have not been studied with care. 



Large specimens of Pyrosoma have also been taken on several occa- 

 sions. Some of these were 15 to 18 inches long, and nearly 2 inches in 

 diameter at the larger end, tapering gradually to the small end. 



The floating masses of sea-weeds {Sargassum and Fucus) are nearly 



always covered with various species of Hydroids and Bryozoa. Among 



the latter is an encrusting species which covers the fronds and bladders 



with a delicate calcareous network, and when the Sargassum is dried 



H. Mis. G7 38 



