100 MR BAIRD ON THE ENTOMOSTRACA OF BERWICKSHIRE. 



cated, about twelve in number. The mai-kings of shell are not in all specimens 

 very distinct. 



15. a. lucens. Nova species. PI. III. fig. 15. — Yetholm Loch and pools on 



Beaumont Water. Shell white, shining, witliout spot ; almost opaque ; ventri- 



cose ; elevated on upper margin towards posterior extremity, and reniform. 

 underneath ; anterior extremity narrower and flatter than posterior, which is 

 arched and broad, the inferior angle being, however, prolonged to a point ; a few 

 fine hairs at each extremity. This species diifers from C. detecta in being ventri- 

 cose, and more arched in upper margin; and from C. Candida in being reniform, 

 in not being ovate, and in want of rigid hairs which beset that species. 



16. C. compressa. Nova species. PI. III. fig. 16. — Yetholm Loch. Shell 



round-shaped, compressed, rather narrower anteriorly than posteriorly ; of a grey 

 colour, more or less deep ; semi-transparent ; at either extremity beset with fine 

 hairs ; in some specimens spotted as if little pieces were hollowed out ; anterior 

 feet provided with several long bristles ; eye large ; antennae terminated by 

 numerous long setse. From the flat compressed shape of shell, its motion through 

 the water is very much like that of some species of Lynceus. 



G-ENUS IV. Daphnia. 



1. Daphnia quadrangula, Muller, p. 90, tab.xiii. fig. 3, 4. Ditch near Berwick. 



2. D. pulp.v, Desmarest, Leach, Latreille. — D. pennata, Muller, p. 82, tab. xii. 

 fig. 4-7. — Monocidus pulex, Linne and Fabricius. — Pulex caudafus, Schaeffer. — — 

 Near Berwick, at Coldstream, and near Routing Linn at Fenton. 



3. D. sima, Muller, p. 90. tab. xii. fig. 11-12. — D. vetuJa, Straus. — Pulex non 

 caudatus, Schseffer. Common about Cockburnspath, Yetholm, &c. 



Gends Y. Lynceus. 



1. Lynceus xphrrricus, Muller, p. 71, tab. ix. fig. 7-9. — Monoculus sphaericus, Fa- 

 bricius. Common in all the ditches and ponds throughout the district. 



2. L. quadrangv.laris, Muller, p. 72, tab. ix. fig. 1-3. In the Pease Burn, and 



in a pool on Beaumont Water at Yetholm. 



3. L. lamellatus, Muller, p. 73, tab. ix. fig. 4-6. — Yetholm Loch, and in a pool 



on Beaumont Water at Yetholm. This is a very fine large species, about the 



size of Daphnia pulex, but Muller's plate of it does not appear to me to be a good 

 one. 



4. L. trigonellus, Muller, p. 74, tab. x. fig. 5-6. — L. laficornis, Desmarest. 



Pond at Foulden, and at Yetholm. 



5. L. truncatus, Muller, p. 75, tab. xi. fig. 4-8. — Pool on Beaumont water at 



Yetholm. Muller says he found this species once in autumn 1782, but never 



met with it afterwards. It appears, therefore, to be a very rare species, and is a 

 very beautiful one. 



6. L. harpcB. Nova species. PI. II. fig. 17. — Pool on Beaumont Water, and in 



Dunglass Pond. Shell harp-shaped ; ribbed longitudinally, the ribs resembling 



the strings of the harp ; rounded posteriorly, sinuated anteriorly, and terminating 

 in a point projecting forwards ; antenna; four, long, nearly the length of the shell, 

 each consisting of three articulations, and terminated by three long linear setae ; 

 shell smooth, except anterior edge where it is situated, being there ciliated ; tail 

 serrated, terminated by two strong setae ; head rounded, and beak blunt. Differs 

 from L. truncatus in sinuated anterior margin of shell, blunt beak, and long 

 antennae ; in not being truncated on posterior extremity ; in wanting the thirteen 

 little teeth at the base ; and in wanting the two thick and large upper feet : differs 

 from L. quadrangularis in shape, in sinuated anterior margin, in more distinci; 

 ribs, and in blunt beak. 



7. L. hama.tus. Nova species. PI. II. fig. 18. — Yetholm Loch. Shell trun- 

 cated anteriorly, and ciliated ; upper part gibbous ; tail not serrated, gibbous, 

 terminated by two setae ; two upper feet large, and each furnished at extremity 

 ■with a strong claw or hook curved upwards ; antennae of three setae each : ap- 

 proaches L. trigonellus, but differs from it in beak being blunted and stronger; 

 in tail not being serrated ; in wanting the strong pedif orm organ below palpi and 

 above the feet ; and in the upper feet having the strong hooks. 



