•iv The Microscope. 



19. ChcL'tonotus enormis, sp. nov. — Plate I, fio-. 12. 

 The upper and lateral surfaces of the head and neck are clothed 

 with short recurved prickles, which also extend along the entire ven- 

 tro-lateral margins of the body. The central and posterior parts of 

 the dorsal region bear thirteen long spines which are posteriorly 

 directed, but only slightly curved. They arise by an enlarged base 

 directly from the cuticular surface without the intervention of scales, 

 and taper to the free extremity near which they are unequally fur- 

 cate. They are arranged as shown in fig. 12, three spines in the first 

 or most anterior transverse row; four in the next following; two 

 widely separated in the third; three in the fourth, while the fifth 

 series consists of but a single centrally located one. On each side pos- 

 teriorly are two long, recurved thorns, belonging apparently to the 

 series of small spines that fringe the margins of the body. The ani- 

 mal measures 3^1,7 inch in length. 



20. Chcetonotus acanthophorus, sp. nov. — Plate I, figs. 13 and 14. 



The superior surface of the head and neck, and the lateral body 

 margins are ornamented by short recurved j)rickles, while the dorsal 

 region proper bears four rows of long recurved thorns, each series arch- 

 ing in a forward direction and consisting of five thorns each, with an 

 additional one on each side of the body near the posterior bifurcation. 

 The thorns are minutely and unequally fm-cate, and arise from an 

 enlarged base (fig. 14), so that the animal is almost completely clothed 

 in an armor formed of the basal enlargements. The oral annulus is 

 not beaded. The egg has not been seen. The body measures o^ 

 inch in length. 



The writer recognizes and regrets, more vividly perhaps than 

 the reader, the absence of strict accuracy in his drawings, and their 

 want of artistic expression. The reader will j^erceive the deficien- 

 cies when he meets with the living creatures in their exquisite per- 

 fection. 



PLATE II. 



Figure 10. Ch. loricaUis, sj). nov.; dorsal aspect; anterior 

 scales omitted. 



Figure 17. Ch. loricatus, illusory appearance of the oral 

 ajierture. 



Figure 18. Ch. loricatus, transverse optic section of the 

 cesojihagus. 



Figure 19. Ch.' loricatus, diverticula within the oesophagus. 



Figure 20. Ch. loricatus, eg^. 



Figure 21. Ch. loricatus, longitudinal optic section. 



