160 Prof. M'lntosh's Notes from the 



are muscular, and perform various movements. Mesnil 

 could not satisfy himself as to the iflentity of Johnston's 

 jyeririe vu/f/aris with De Quatrefage's Malacoceros vulgaris 

 vel Scolecolepis girardi. lie ])oiiits out that what was sent 

 to him from Heligoland as Serine vulgaris, Johnston, pprtains 

 to Scolecolepis fuiiginosa, C\a.]rdrede. Ehrenbaum, he states, 

 considered the Aonis wagneri of Leuekart as identieal with 

 the supposed Nerine vvlgaris, and Mesnil thought Colobranchus 

 ci'iatus, Keferstein, a distinct form, a view not now held. 



The fourth British species is FcolecolepSis fuliginosus, 

 Claparede, in which the head in lateral view is more pointed 

 than in Scolecolepis vulgaris, and in.lront has a median cleft. 

 The constriction behind the broad base of the frontal 

 tentacles is more marked. A cream-coloured patch occurs 

 on the prostomium, with black pigment on that region and 

 on the dorsum as well as on each side of the moutii. Tlie 

 pal()i have dark bands. The body is about 3 inches long, 

 smaller, as a rule, than Scolecolepis vu'goris, with longer 

 branchicC anteriorly, and it tapers a little in front, but much 

 more posteriorly, where it ends in a vent with 8 flattened 

 cirri. The segments numerous — 150 to 160. 



The first foot carries a larger branchia than in S. vulgaris, 

 and the superior lamella is narrower and the tip more acute, 

 whilst the infeiior lamella is also narrower and more pro- 

 minent. The bristles are similar, but more delicate. At 

 the 10th foot the branchia is a long, richly ciliated process, 

 the upper lamella is hatchet-shaped, pointed and free 

 superiorly, the inferior lamella beiug capstan- shaped. The 

 long bri.<tles at the upper edge of the dorsal tuft have 

 narrow wings, and the shorter forms, dorsally and ventrally, 

 are finely tapered. The branchia and superior lamella 

 diminish before the 50th foot, about which foot three or four 

 winged hooks appear in the ventral division. These hooks 

 diti'er from those of Scolecolepis vulgaris in the larger angle 

 made by the main fang with the neck, in its rather blunt 

 tip, and in the presence of only a single spine on the crown. 

 The ventral hooks and associated short bri>tles continue to 

 the posterior end. This form is not uncommon in the south. 

 JVlesnil makes two varieties, viz. var. microchceta from Naples, 

 and macroclKEta from the Channel, and further two sub- 

 divisions, viz. minor and major, but such distinctions are 

 mainly of interest in demonstrating the variability of the 

 species. 



The fifth member of the group is Scolecolepis {Laonice) 



