of the Fishery Board for Scotland. 255 



Habitat. — Off Limekilns, west of Queensferry. Washed from lumps of 

 hardened mud. Not very common. 



This species appears to be extensively distributed throughout the 

 British Islands. 



Dactylopus coronatus, sp. n. (PI. IX. figs. 12-20.) 



Description. — Female. Length, *57 mm. (^th of an inch). Body 

 moderately robust. Anterior antennae short, stout, six-jointed, and bear- 

 ing numerous elongate and stout, plain, and spinulose setae (fig. 13). The 

 ante-penultimate joint is rather shorter than any of the others, and bears 

 a long stout filament. The formula shows the proportionate lengths of 

 the joints : — 



13 • 17 • 12 • 8 • 11 • 10 • 

 1 • 2 • 3 • 4 ' 5 • 6 ■ 



Posterior antennae short and stout. Secondary branch two-jointed, strongly 

 setiferous. Mandibles somewhat like those of Dactylopus tisboides, Claus. 

 The biting part is armed with a broad trifid tooth, two spiniform teeth, 

 and a few setiferous spines (fig. 15). Posterior foot-jaws robust. A strong 

 setiferous spine springs from the inner distal angle of the first joint. 

 Terminal claw stout, curved, scarcely equal in length to the joint from 

 which it springs. Both joints are furnished with rows of cilia, as shown in 

 the figure (fig. 16). All the swimming-feet are short and stout, but those 

 of the first pair are more robust than the others. The first joint of the 

 inner branches of the first pair is considerably dilated, and longer than 

 the next two together, and furnished with a plumose seta near the middle 

 of the inner margins. The second and third joints are sub-equal, and much 

 narrower than the first joint. The second joint bears a seta similar to that 

 of the first joint. The third joint bears a small marginal plumose seta, a 

 terminal plumose seta, and two elongate curved terminal spines. The 

 outer branches are nearly equal to the length of the first two joints of 

 the inner branches. The first two joints are sub-equal, but the last is only 

 about two-thirds the length of the preceding one (fig. 17). The middle 

 joint of the outer branches is furnished with a long plumose seta near the 

 end of the inner margin. The spines on the outer margins of the first and 

 second joints are moderately stout and setiferous. The outer one of the 

 five terminal spiniform setae is about the same length as the marginal 

 spines, but the others become gradually more elongate, so that the inner 

 one is fully three times the length of the outer (fig. 17). The inner 

 branches of the second, third, and fourth pairs are shorter than the outer 

 branches, and both are furnished with several plumose setae on the inner 

 margins, while the outer margins are strongly ciliate. The marginal spines 

 of the outer branches are all more or less setiferous (fig. 18). The fifth 

 pair are each indistinctly two-branched (or two-jointed) and foliaceous. 

 The joints are sub-equal, and are each furnished with five stout plumose setae 

 of various lengths round the distal end. Caudal stylets short. One ovisac. 



Habitat. — Among dredged material from the Rath ground in the 

 vicinity of the Bass Rock ; also in dredged material from Largo Bay. 

 ISTot common. 



Remarks. — The structure and armature of the anterior antennae are 

 alone sufficient to distinguish this from other species of Dactylopus. 



Genus Thalestris, Claus (1863). 



Thalestris forficidoides, T. and A. Scott. (PI. X. figs. 13-25.) 



1894. Thalestris forficidoides, T. and A. Scott (31), p. 142, pi. 

 ix. figs. 4-9. 



Description. — Female. Length, 73 mm. (Jj-th of an inch). Anterior 



