222 ANNALS OF SCOTTISH NATURAL HISTORY 



Gen. LEPTOSTYLIS, G. O. Sars, 1869. 



(25) LEPTOSTYLIS VILLOSA, G. O.Sars. A number of specimens 

 of this small Cumacean were obtained in a tow -net gathering 

 collected in April 1896, in about 40 fathoms, between Arran and 

 the coast of Ayrshire. There is no previous record of this species 

 from the Firth of Clyde, and it is also an addition to the British 

 fauna. The members of this genus have a much smaller telson than 

 Diastylis, and the abdomen and uropods are proportionally more 

 slender. In Leptostylis villosa the serration of the anterio-lateral 

 margins of the carapace is peculiar ; the " teeth " are not like those 

 of a saw, but are rather hatchet-shaped ; the margins here are 

 perforated at slight intervals, and j each perforation widens inwardly 

 and ends in a rounded base, and thus each "tooth" is wider at the 

 outside edge than it is inside. Sars describes these serrations as 

 lamellar. 



Fam. VII. PSEUDOCUMID^E. 

 Gen. PSEUDOCUMA, G. O. Sars, 1865. 



(26) PSEUDOCUMA CERCARIA (van Benedeii). This is a gener- 

 ally distributed and moderately common species, and is generally 

 more frequent in shallow sandy bays, but is also found in deep 

 water. I have notes of its occurrence from almost every portion of 

 the Scottish coast examined by me, i.e. the Firth of Forth, the 

 Moray Firth, the Firth of Clyde, etc. 



(27) PSEUDOCUMA SIMILIS, G. O. Sars. I have obtained this 

 species in a gathering of Crustacea from moderately deep water near 

 the mouth of the Firth of Clyde, collected on ;th December 1899, 

 but only recently examined, only a single specimen a female was 

 observed. This species resembles Pseudocuma cercaria so closely, 

 that it has only lately been recognised and described by Professor 

 Sars. Now that its characters have been disclosed, its identification, 

 when examined under the microscope with a ^ or \ inch objective, 

 is comparatively easy. It may be distinguished from Pseudocitma 

 cercaria by the following characters : (i) the rostrum (pseiidorostral 

 projection] is less produced, and therefore its lateral margins are 

 much less oblique, being nearly at right angles to the dorsal edge ; 

 (2) at the anterio-lateral corners of the pseudorostral projection, 

 where the oblique lateral plicae of the carapace terminate, there are 

 three small but distinct teeth ; (3) the basal stem of the uropods 

 is proportionally longer, being at least equal in length, if not fully 

 longer than the branches. 



Gen. PETALOSARSIA, Stebbing, 1893. 



(28) PETALOSARSIA DECLIVIS (G. O. Sars). This small species 

 was taken in the Firth of Forth (Largo Bay) in March 1891, in the 



