NEW AND RARE SPECIES OF COPEPODA FROM SCOTLAND 33 



and broader, and by the difference in the structure of the 

 first and fifth thoracic feet. The ovisac of this species 

 appears to contain fewer but larger ova than that of Lepto- 

 psyllus robertsoni. 



RECORDS INDICATING AN EXTENSION OF DISTRIBUTION. 



CYCLOPS ^EQUOREUS, Fischer, " Abhandl. der Akad. der 

 Wissenschaft," Bd. viii. p. 654, Taf. XX., Figs. 26-29 (1860). 

 This, which is one of those curious species that form a 

 link between the truly freshwater and the truly marine 

 Copepoda, was obtained in brackish pools near the head of 

 West Loch Tarbert, Argyleshire, on both the north and 

 south sides of the loch. Though widely distributed, the 

 Scottish localities where Cyclops csquoreus has been recorded 

 from are, so far as known to us, few in number. It has been 

 " taken by the Rev. A. M. Norman in the West of Scotland"; 1 

 in pools above high-water mark at Cramond Island, Firth of 

 Forth ; in the mussel beds at the mouth of the river Eden, 

 Fifeshire ; and Loch Stennis, Orkney. 



TACHIDIUS LITTORALIS, Poppe. [TACHIDIUS CRASSI- 

 CORNIS, T. Scott, " Tenth Annual Report of the Fishery 

 Board for Scotland," part iii. p. 250, Plate VIII. Figs. 14-27 

 (1892).] 



Tachidius littoralis was recorded from the Firth of Forth, 

 the first time for Scotland, in 1892. Though as yet known 

 from only a few localities in the British Islands, we believe 

 that it will yet be found distributed all round our shores 

 wherever there is a suitable habitat, i.e. brackish water with a 

 muddy and weedy bottom. It was obtained in pools of this 

 description during the month of July last year around the 

 head and north side of West Loch Tarbert. 



DELAVALIA PALUSTRIS, Brady, " Nat. Hist. Trans. North- 

 umb. and Durham," iii. p. 134, PL V. Figs. 10-15 (1868). 

 This species was taken in pools between tide -marks near 

 the head of West Loch Tarbert. Its distribution in Scotland 

 appears as yet to be very limited. The Firth of Forth is 



1 " A Monograph of the Free and Semiparasitic Copepoda of the British 

 Islands," ii. p. 120 ; no locality is given. 

 I 3 D 



