[25] ALBATROSS EXPLORATIONS. 527 



V. & S. (fig. 96), Margarita regalis Y. & S. (fig. 97), M. lamellosa Y. & S. 

 (fig. 98), and by several small species of Cyclostrema. A more peculiar 

 group includes curious small limpet-sbaped shells, not distantly allied 

 to Fissurella, but imperforate at tip. Of these we now know 10 species 

 from our deep dredgings. These belong to the genera Addisonia, 1 spe- 

 cies; Goeculina, 6 species; Lepetella, 1 species; Fropilidium, 2 species. 



The Tectibranchs are relatively abundant in deep water, one of the 

 shell-less species, Koonsia obesa Y. (fig. 107), grows to a very large size, 

 some examples being 4 to 5 inches long and 3 broad. A large and 

 handsome new Scaphander {8. nohilis Y., fig. 106) was taken alive in 

 1,058 to 1,309 fathoms. 



The Scaphopods are much more numerous in deep than in shallow 

 water, and are abundantly represented by several species of Dentalium, 

 Siphodentaliuni, and Cadulus (fig. 126). D. solidum, from 843 to 1,309 

 fathoms, grows to the length of 3 J inches. Cadulus grandis Y. and another 

 allied new species^ ((7. princeps Y.) are remarkably large representatives 

 of this genus. The former lives in 816 to 1,537 fathoms, the latter in 

 1,525 to 1,594 fathoms. 



Of Heteropoda, eight species were taken, including at least six species 

 of Atlanta (figs. 110, 111). Part of these were only dredged as dead 

 shells, but others were taken alive at the surface. Two transparent 

 species of Firola (fig. 112) and Firoloides were common at the surface, 

 associated with Sagitta, which it somewhat resembles in shape. AH 

 these species, except one, and most of the twenty-three Pteropods have 

 long been known from the more tropical parts of the Atlantic, but not 

 from so far north. 



The bivalves or Lamellibranchs are relatively less abundant than in 

 shallow water, and are less peculiar ; but they include numerous species 

 of the Anatinidse and Corbulidae (especially the genus Newra), the Ku- 

 culidae, including the genersb Nucula, Leda, Yoldia^ Glomus, Malletia,&G.', 

 and ^he Arcidse, including Area and Limopsis. The Luciuidse are also 

 well represented by several species of Cryptodon (or Axinus) and other 

 genera. Among the most peculiar forms are Fholadomya arata (figs. 

 133, 134), Mytilimeria fleocuosa (fig. 132), Verticordia ccelata (fig. 131, a), 

 and Poromya sublevis (fig. 128). Several species of Fecten and Amussium 

 also occur, most of them with delicate, translucent, and elegantly sculp- 

 tured shells (figs. 141, 142). 



Of the Brachiopoda we took two deep-sea species, both new to our 

 coast, but known on the European side. These are Waldheimia cranium^ 

 in 1,362 fathoms, and Discina Atlantica, in 1,251 to 1,467 fathoms.* 



The accompanying tables will give an idea of the number and bathy- 

 metrical distribution of the difterent groups of MoUusca. 



The writer's published listt of the MoUusca taken in 1880 to 1883 by 



•An additional species was obtained in 1884: Atretia gnomon, in 1,525 to 1,594 

 fathoms, 

 t Transactions Connecticut Academy, vol. vi, p. 263, 1884. 



