TAXONOMY AND DISTRIBUTION 



133 



distant, equal, wide claws. These arise from a concave- 

 conical (52 ) collar with a length of about 1 oral diameter. 

 The long shaft has a diameter at the lower end of the collar 

 of somewhat less than 0.5 oral diameter, and decreases regu- 

 larly and evenly, without local modifications in contour, as a 

 cone (2 ) to the aboral end. There are 8 long, narrow, 

 ridgelike fins extending from the aboral end for 0.45 total 

 length. There is an inconspicuous aboral cylinder around 

 the open aboral end. 



The wall is hyaline and about 0.0 1 oral diameter in 

 thickness. 



There are 2 oval macronuclei. 



Length, 400U. 



The number ol fins and claws is variable. 



Salpingacantha undata lacks the suboral alae of 5. ampla, 

 and averages shorter and stouter. Its claws are also fewer 

 and larger, and the fins are fewer. It is longer than other 

 species and has a better developed collar and fewer teeth. 



Recorded from two stations, one each in the Atlantic and 

 the Pacific, as follows: one (33) in the Caribbean Sea, and 

 one (80) in the Galapagos region. 



Moth arc pump samples taken at 50 meters. Frequency, 

 minimum. 



Temperature: Atlantic, 28.25; Pacific, 26?o6. Salinity: 

 Atlantic, 36.19; Pacific, sS-')S- Density: Atlantic. 2^.23; 

 Pacific, 23.75. pH: Atlantic, 8.24; Pacific, 8.19. 



