452 A. E. Verrill — Marine JSTemerteans of N'ew England. 



well rounded at the end. The long slender proboscis is partially 

 protruded, so as to show the bulb and sac in the exserted part, but 

 not at the end ; there appears to be a small stylet, but the mounted 

 sj)ecimen is not sufficiently transparent to show its foi'm ; the ex- 

 terior of the exsert proboscis is finely papillose. The large pro- 

 boscis-sac extends back to about the posterior fourth ; it is abruptly 

 narrowed near the posterior end, and a band of muscular fibers near 

 the end, on each side, binds it to the bodjj- wall. A single specimen 

 was taken by the Albatross at each of the following stations : 



Station 2428, N. lat. 42° 48', W. long. 50° 55' 30", in 82G fathoms. 

 Young. 



Station 2724, N. lat. 36° 47', W. long. '73° 25' 00", in 1641 fathoms. 

 Adult. 



EXPLANATION OF PLATES. 



Plate XXXIII. 



Figure 1. — Amphiporus angukdus. Dorsal view with the proboscis partially pro- 

 truded, natural size; !«, the same, ventral view of the head and anterior part 

 of the body. Eastport, Me., low- water, Aug. 7, 1872. 



Figure 2. — The same. Dorsal view of a specimen of the reddish brown variety, more 

 enlarged. Massachusetts Bay. 



Figure 3. — Amphiporus multisorus, sp. nov. Dorsal view of the head and anterior 

 portion of the body ; x 2. Kastport, Me. 



Figure 4. — Amphiporus vircscens Y. Dorsal view; x .'5. Noank, Conn., July 24, 

 1874; 4a, the same specimen, posterior end, more enlarged ; Ab, the same, ven- 

 tral view of the head, more enlarged ; 4r, the same, dorsal view, more enlarged ; 

 id, the same, head with the slightly protruded proboscis ; x 8 ; 4e, the same, 

 nearly profile view of the head ; x 8. Wood's HoU, Mass., July 13, 1875. 



Figure 5. — Amphip>orus ochraceus Y. Dorsal view ; x 4 ; 5a, the same, central 

 stylet of the proboscis, much enlarged. Wood's Holl. 



Figure 6. — The same. Head and anterior portion of another specimen more con- 

 tracted ; X 6. Eel Pond, Wood's Holl, July 19, 1875. 



Figure 7. — Amphiporus cruentaf us Y . Dorsal view; x 3. Noank, Conn.. July 14, 

 1874 (No. 740).. 



Figures. — The same. Doreal view of a larger specimen : x 6; 8«, head of the 

 same specimen, more enlarged. Wood's Holl. 



Figure 9. — Tetrastemma candidum. Dorsal view of a greenish specimen ; x 6. 



Figure 10— The same. Dorsal view of a specimen of the yellow variety; somewhat 

 compressed under the microscope; x 3, low-water; 10a, the same specimen, 

 showing variation in the form of the head owing to the different degree of 

 extension. Casco Bay, low-water, 1873. 



Figure 11. — Tetrastemma vermiculus, var. Dorsal view ; x 7; 11 a, 1 1 ft, other views 

 of the head of the same specimen in different states of contraction ; lie, probos- 

 cis-armature of the same, much enlarged. Wood's Holl, on piles of wharf, July 

 24, 1875. 



Figures 1, 2, and 10 are by J. H. Emerton ; figures 3, 4a to 4e, and 11 to lie, are by 

 the author; the rest are by J. H. Blake. All are from living specimens. 



