200 EXPEDITION OF THE "ALBATROSS," 1899-1900. 



temp. 66\ Four specimens of the aggregate generation were collected on 

 the surface at night. 



Three are about 1 cen. in length and have rather narrow muscle bands. 

 One of these has the posterior extremity prolonged into a prominent process 

 about 1 mm. in length. The fourth specimen is 2 cen. long and has much 

 broader muscle bands than the otlier three. 



Stn. 12 A.A., Sept. 4, 1899, Lat. N. 12" 07', Long. W. 137° 18', surface 

 temp. 81°. One specimen of the aggregate generation was collected. It is 

 1.5 cen. in length,'with a process at the posterior end measuring 5 mm. 



Stn. 15 A.A., Sept. 8, 1899, Lat. N. 4° 35', Long. W. 136° 54', surface 

 temp. 79°. One specimen of the solitary generation was taken at 8 p. m. 



Stn. 31 A.A., Sept. 19, 1899, Lat. S. 12° 20', Long. W. 144° 15', surface 

 temp. 80°. 



One specimen of the solitary generation and four of the others have a 

 short bifid process. 



Salpa hexagon a Quoy et Gaim. 



This species was collected at three stations in the tropical Pacific. 



Stn. 8 A.A., Sept. 2, 1899, Lat. N. 17° 13', Long. W. 136° 09'. A single 

 yoimg specimen of the solitary generation was taken in the trawl, which liad 

 been down to a depth of 3088 fathoms. It measures 11 cen. in length, ex- 

 clusive of the two posterior processes which are 1 cen. long, and is 3 cen. in 

 breadth. This makes it almost exactly twice the size given by Traustedt in 

 his description of the species. The processes, however, in Traustedt's figures 

 are about } the length of the body and are serrate. In this specimen the 

 processes are only ^^ of the length of the body and are smooth. In all 

 other respects the specimen agrees perfectly with Traustedt's figures. 



Stn. 12 A.A., Sept. 4, 1899, Lat. N. 10° 57', Long. W. 137° 35', surface 

 temp. 81°. Fifteen specimens of solitary generation were collected. 



They are all young with a large part of the eleoblast still present. Their 

 average length is 3 cen. and the processes at tlie posterior end are ^ of the 

 length of the body. 



