108 MODERN Sl'STEM. 



Genus 21. N^T.SA. LeacJi. 

 Tail on each side of the last segment, with a straight subcom pressed 



process attaclied to a peduncle : bodj/ six-jointed, the last joint largest: 



antauKE setaceous, sulicqual; upper ones with a very large biarticu- 



lated peduncle, the firbt joint largest: space between the antennae 



easily to be discerned: c/«a;.s bifid. 

 Sp. 1. NiE. hidentata. Last segment of the body armed with two spines 



or teeth; colour cinereous, faintly streaked with blue, or reddish. 

 Oniscus bideniatus. Adams, Trans. Linn. Sgc. v. 3. f. I.f. 3. Is'asabi- 



dentata. Leach, Edin. Etici/cL wii. 405. — T7-a7is. Linn. Soc.xi. V>67.^— 



Supp. to Encycf. Brit. i. 427. 

 Inhabits the coasts of Wales and Devonshire. 



Stirps 2. Tail with two lamoll^'E on each side. 



* Superior antenntc 7cith a vay la?'gc peduncle. Clares bifid. 



Genus 22. CYMODICE. Uach. 



Eyes touching the anterior margin of the first segment of the body: 

 /'Of/j/ seven-jointed : tail at the base, on each side with two subconi- 

 pressed but not i'oliaceous appendages, the exterior ones largest; the 

 apex of the tail notched, with a lamella in the centre: dazes bifid. 



Sp. 1. Cij.ti-uncuta. Apex of the tail truncate. 



Oniscus truncatus. ]\hmtagris MSS. Cymodice truncata. Leach, Edin. 

 Enctjcl. vii. -133. — Trans. Linn. Soc. xi. 303. — Saj)p. to Enct/cl. Brit. 

 i. 427. 



This species is very rare, and has been found but three times on 

 the southern coast of Devonshire. 



Genus 23. DYNAMENE. Leach. 

 Eyes not reaching to the anterior margin of the first segment of the 

 body: hody seven-jointed: /«//with two equal ioliaceous appendages 

 on each side of its base; the a])cx notched : dazes bifid. 

 Dynamene. I^ach, Edin. Encycl. vii. 433. 



There arc several indigenous species of this genus, and their cha- 

 racters will be given luiderthe article Cymotuoade'es, in the Dic- 

 tionnaire dcs Sciences Naiiaxllcs, by Dr. Leach. 



Genus 24. SPILEROMA. Lafr., J^ach. 

 Eyes not reaching to the anterior margin of the first segment of the 



body : body seven-jointed : tail with its apex entire ; the l)ase on each 



side with two equal foliaceous appendages: daws bifid. 

 Sp. 1. Sph. scrruta. Body smooth, un;irmed: tail very smooth on each 



side; obliquely truncated : lamelke elliptic, acute, the external ones 



externally serrated. 

 Oniscus Globator. Pall. Spec. Zool.fasc.ix. t. 4. f. 18. Cymothea ser- 



rata. I'abr. Ent. Syst. ii. 510. Sphceroma cinerea. Latr. Gen. Crust. 



