454 Part III. — Twentieth Annual Report 



somewhat from the fifth pair of the male of Phcenna spinifera, Glaus, 

 especially in the terminal part of the left branch, when compared with 

 the figure of the male fifth pair in Dr. Giesbrecht's work * ; and I have 

 therefore provisionally retained it under a separate specific name. 



Centropagid^e. 



Metridia longa (Lubbock). PL XXII., figs. 1-4. 



One or two specimens of Lubbock's Metridia (Calanus) longa were 

 found in a gathering collected about 22 miles to the north and in another 

 collected about 60 miles to the east of the Shetland Islands ; the first was 

 collected on May 17th, and the other on May 22nd, 1901. One of the 

 largest specimens taken in the first gathering measured 4 mm., or about 

 one-sixth of an inch in length. The male and female specimens 

 represented by the drawings (figs. 1. to 4) were obtained in the second of 

 the two gatherings mentioned above ; this female, which is scarcely so 

 large as the largest specimen found in the first gathering, measured about 

 3*7 mm. and the male 2*8 mm. in length. The fifth pair of thoracic feet 

 of the male and female, as represented by the figures 3 and 4, are 

 practically identical with the figures of the same appendages given by 

 Dr. Giesbrecht.f 



Metridia lucens, Boeck. 



This species was moderately frequent in the same gatherings with the 

 last, as well as in gatherings from the Moray Firth and from other parts 

 of the Scottish coasts. 



PSETJDOCYCLOPIDiE. 



Pseudocy clops obtusatus, G. S. Brady. 



One or two specimens of this curious species occurred in the washings 

 of some dredged material from the north-west end of Inchkeith, Firth of 

 Forth, collected on May 23rd, 1901. Pseudocyclojps obtusatus has already 

 been recorded from the Forth estuary, but has not been very often met 

 with. 



PONTELLIDiE. 



Acartia bifilosa, Giesbrecht. 



Acartia bifilosa was obtained along with the two species of Metridia 

 mentioned above in the gatherings from the north and east of Shetland, 

 and also in gatherings from the Firth of Forth recently collected. 



CYCLOPIDyE. 



Oithona (?) setiger, Dana. 



Several specimens of an Oithona which I ascribe to Oithona setiger, 

 Dana, occurred in a tow-net gathering from the Firth of Forth collected 

 on April 22nd, and also in a similar gathering collected to the east of the 

 Shetland Islands on the 22nd of May, 1901. In these specimens the 

 rostrum, which projects forward instead of downward as in 0. 

 helgolandica, Claus (0. similis, Giesbrecht), tapers gradually to an acute 



* Fauna u. Flora d. Golfes v. Neapel, vol, 19, p. 293, t. 12, fig. 5. 

 f Pelagischen Copepoden dcs Golfes von Neapel, pi. 33, figs. 20 and 23. 



