Gatty Marine Laboratory , St. Andrews. 45 



directerl downward and backward, or just in front of the 

 tail downward and forward. In these elongated bristles 

 the wings are indistinguishable. A few shorter bristles, 

 probably in process of development, occur in these tufts. 



The striated shafts of the long anterior hooks are even 

 more tapered at the insertion than in Cfauveli^owA. they 

 increase in diameter upward to the shoulder, which gently 

 diminishes to the stout neck. The great fang leaves the 

 throat nearly at a right angle, and on the crown above it in 

 lateral view are five or six teeth. The neck and shoulder of 

 these hooks have a forward curve, so that the head is carried 

 backward. The posterior hooks have a convex anterior and 

 a concave posterior outline, but the base is not bent back- 

 vrard as in the ordinary aviculariau forms. The main fang 

 leaves the throat at somewhat less than a right angle, and 

 is strong and sharp. Above it is a series of four or five or 

 more small but distinct teeth. The slightly-curved neck 

 dilates a little as it merges into the stunted shaft or base, 

 which has a slight flexure backward, the character of the 

 hook being thus diagnostic, and so different from those of 

 species of C/ione hitherto described. In a variety from 

 Finmark the bases of these hooks are tapered into shaft-like 

 processes, and the whole series constitute in each foot an 

 elegant fan. They form a single row. 



Chone filicaudata, Southern, from Clew Bay, Ireland, is 

 the seventeenth species, and differs from Chone duneri, 

 Malmgren, which it approaches in the presence of a bifid 

 process of the lip-membrane, in the form of the posterior 

 hooks, which have a higher crown and more numerous teeth 

 above the great fang in lateral view. It also has a conical 

 anal appendage. The terminal process of the branchial 

 filament has a central axis and a web on each side. It is the 

 rule, however, for the posterior hooks in most species of this 

 genus to have higher crowns. The occurrence of a caudal 

 filament on Chone duneri in certain cases, however, makes 

 the distinction less evident, yet the posterior hooks diverge. 



Jasmineira elegans, De St. Joseph, a southern form, is the 

 eighteenth species. The cephalic lobe, when the branchiae 

 are removed, presents a mushroom-shaped basal region — 

 tiiat is, it is constricted proximally and dilated distally, and 

 has a median cleft. It is marked externally by longitudinal 

 lines or grooves. From the ventral edge of each half three 

 or four slender smooth tentacles (four to six, De St. Joseph) 



