70 



2. ^geon sculptus (Bell sp.). 

 ■M^. Eostro satis longo, apice bifido, profunde sulcato. Orbibus 

 dense ciliatis. Carapace, quinquedentato carinato. Abdominis somiti- 

 bus sculptis, tertio ad quintum etiam carinatis, sexto etiani bicarinato- 

 sulcato. Telson profunde sulcato. Chelipedum pare secundo quam 

 tertio, multo breviori. Syn. Cran^on sculptus {Bell). Littoris Hibernise 

 et Magnae Britannige. 



Genus IY. 



JN^ectocrangon (Brandt.). E'ondum in maribus Britannicis inventus, 

 Syn. Argis (Kroyer) Crangon, (Owen), sp. Ned. Lar. 



Homologies of Ckangonii)^ Plate III. 



Geneeal Eefehences 1, 2, &c., refer to the somites and their 



appendages, the ocular ring being counted the first ; the coxse are re- 

 presented as attached to the somites, coc, coxa; h, basis; i, ischium; 

 m, meros ; c, carpus ; p, propodos ; d, dactylos ; g, gastric region ; cd, car- 

 diac do. ; h, hepatic do. ; hr, branchial do. ; /, frontal do. ; A, Abdomen ; 

 'K9, Cephalothorax and it appendages; Md 4, lateral view of carapace; 

 1, first, or ocular segment; 3, olfactory antennal do.; 2, auditory an- 

 tenna ; 4, mandible ; md'", back view of carapace ; Q, somites of mouth 

 organs and their appendages; E, do. of ambulation; 10, 11, 12, first, 

 second, and third chelipeds; those of 13-15 resemble 12 ; I, outline 

 rostrum, C. vulgaris. — II. Ch. spinosus. — III. Ch. bispinosus. — IY. 

 M. fasciatus. — Y. sculptus. — YI. Ch. cataphractus. 



Family— CEAI^GOi^ID^. 



Carapace depressed ; rostrum short, not articulated ; eyes not con- 

 cealed beneath carapace; external antennae unifilamentous, furnished 

 with a broad scale at their base ; internal antenneo dilated at base, pe- 

 duncle short, bifilamentous ; external maxillipeds subpediform, flattened. 

 Chelipeds, five pairs ; first pair subcheliform, second didactyle ; third to 

 fifth pairs simple, acuminate. Branchiae, seven on each side ; antennae 

 inserted nearly on same line. Genera : Crangon, Cheraphilus,^geon. 



Genus I. — Ceangon. 



Eostrum triangular, shorter than the eyes. Carapace : median gas- 

 tric region armed with a single spiny tooth at most ; branchial regions 

 with a single tooth, not ridged ; antennae as family ; abdomen smooth 

 above ; telson triangular, smooth above ; orbits circular, sparsely pu- 

 bescent : first pair chelipeds weU developed ; second pair as long as fifth ; 

 antennal scale large. British Species : Cr. vulgaris. 



In addition, as minor characters, the following are nearly general : — ■ 

 Antennae long — more than twice length of peduncle of antennae. Se- 

 cond pair of chelipeds as long as third, which are moderately stout. 



