DB BAIKD ON £NTOMOSTRACA. 149 



Genui Ist. — MaoBOTBBIX — Baird* 



Superior antennce flat, having only one articulation. Inferior 

 antenncB large, two-branched, each branch having three articu- 

 lations. Second articulation of anterior branch, provided with 

 a very long seta or filament. Eye accompanied with a black spot 

 situate in front of it. 



Sp. 1st. — ^M. roseus — Monoculus roscus, Jurine.^ 



This species has been taken by Sir W. Jardine, in Lochmaben 

 Loch, Dumfriesshire, where it appears to form, in part, the food 

 of the vendace. 



Sp. 2d. — M. laticomis, Baird.X Monoc. laticomis, Jurine. 

 Daphnia Curvirostris, Muller. Entomost. 



Genus 2d. — BosMiNA. 



Inferior antennae large, two-branched, one branch having four, 

 the other three articulations. Superior antennae, long, curved, 

 round, and many-jointed. 



Sp. 1st. — Bosmina comuta — Monoculus comutus, Jurine.^ 

 Daphnia comuta, Baird, Lynceus longirostris ? Muller, En- 

 tomost 



FAMILY 3.— POLYPHEMID^. 

 Four pairs of feet, not contained within the shelL Eye very 

 large. Lower part of shell forming a large vacant space for con- 

 taining the ova and young. 



Genus 1st, — PoLTFHEMUS — Muller, 



Head distinct from body ; abdomen projecting externally from 

 shell. Inferior antennae or rami large, two-branched, one branch 

 having three, the other four articulations. 



Sp. 1st. — Polyphemus oculus. Mull, Entomost. Polyphe- 

 mus stagnorum, Leach. Polyphemus pediculus, Straus. Cepha- 

 loculus stagnorum, Lamk. Monoculus pediculus, Linn. Mon. 

 polyphemus, Jurine. 



Genus 2d, — Eyaoke — Lwen, 

 Head not distinct from body. Abdomen inclosed within the 



♦ Ann. Mag. Nat. Hist. f Hist, dee Monoc., Ac., t. 15, f. 4-6. 



: Ibid. § Ibid. 



B. N. C. ^VOL. II. NO. XJII. M 



