202 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
D. tisboides the anterior antenne of the latter however is 
nine jointed, that of D. strom being eight jointed. 
Dactylopus tenwyrenus, Brady& Rob. Pl. XXII, fig.4.¢.d.) 
Length 0.80 mm. One specimen only taken by surface 
townet near Port Erin. Its caudal segments (d) form a 
distinguishing feature. 
Dactylopus flavus, Claus. (Pl. XXIII, fig. 5. a—d.) 
Length 0.80 mm. This is evidently a rare species. 
We have occasionally taken it, by dredge off or near the 
Calf of Man in 20 fathoms. It is of a dark yellow colour 
and easily recognizable by its short compact somewhat 
boat-shaped appearance. 
Dactylopus brevicornis, Claus. (Pl. XXII, fig. 4. e. f. g.) 
Length 0.60 mm. A few specimens were found in tidal 
pools at Douglas, Isle of Man. The short, densely setose 
anterior antenne at once distinguish it from others of 
the genus. 
Dactylopus minutus, Claus. (Pl. XXII, fig. 5. e. f.) 
Length 1.mm. A single specimen was dredged in 20 
fathoms near the Calf of Man. It is evidently one of the 
rarest species of the genus. 
Thalestris helgolandica, Claus. (Pl. XXII, fig. 7.) 
Length 0.80 mm. A few specimens have been dredged 
off the Little Orme and near Puffin Island, also in Port 
Erin Bay. ‘The presence of a middle joint in the inner 
branch of the posterior antenne and the shape of the 
fifth feet sufficiently distinguish this species. 
Thalestris rufocincta, Norman. (Pl. XXII, fig. 6.) 
Length 1.25mm. Common both free swimming and 
in dredged material throughout the district. It is of a 
yellowish colour, the edges of the body segments being 
usually lined with crimson. ‘This together with the 
plumose character of the spines on the swimming feet (@) 
easily distinguish it. 
