Crustacea. 3765 



A few of those I collected were young specimens, about half grown, and these had no 

 sign of the triangular mouth, or the reflexed lip, which characterize the species when 

 full grown. — William Henry Hawker ; Ashford Lodge, Petersfield, Hants, December 

 2%, 1852. 



Description of a Young Lobster measuring only nine lines. — Generic character : — 

 External antennae not so long as the body: arm longer than the hand; inner margin 

 toothed : anterior legs long, slender, equal ; fingers long, slender, toothed; second and 

 third pairs of legs didactyle, fourth and fifth monodactyle : rostrum wide, deeply groov- 

 ed, armed on each side with four teeth, the sides parallel for two thirds of its length, and 

 then tapering off to an acute angle, the apex trifid : carapace more nearly cylindrical, 

 the segments terminating laterally in an acute triangular process produced to a spine. 

 Specific character : — Body thick and rounded : cephalothorax deeper than broad, com- 

 pressed at the sides ; a furrow separates the gastric from the posterior regions ; the la- 

 tere- posterior portion is slightly punctuated : rostrum projecting beyond the peduncle 

 of the external antennae, wide and deeply grooved throughout, of even width through 

 half its length and then running to an acute trifid apex ; the carina on each side form- 

 ed by the groove is toothed with three spines ; that portion of each carina which ex- 

 tends on to the cephalothorax bears about a dozen teeth : rostrum straight, recurved 

 at the extremity : eyes large, forward, completely protected by the rostrum : a small 

 tooth on each side of and even with the base of the rostrum : external antennae about 

 two thirds as long as the body : abdomen semicylindrical, segments smooth, terminat- 

 ing on each side in a flattened triangular plate, which ends with an acute spine ; the 

 margins of the plate are toothed with very fine and numerous teeth ; the three poste- 

 rior segments are more spread than the others, thus giving a semi-oval appearance to 

 that portion of the carapace : tail broad ; the exterior laminae strongly divided at their 

 anterior third ; the margin of their posterior portion dentated ; two round carina? start 

 from a point at the base of the centre lamina, and, diverging, end at its extremity in 

 a tooth at each corner, thus forming a triangular space between them : anterior legs 

 large, equal, quite smooth, with the exception of the inner margin of the arm, which 

 is toothed : arm as long as the hand ; wrist one-third as long as the arm ; hand about 

 four times longer than broad ; fingers almost as long as the hand, straight, and hav- 

 ing numerous small teeth : the remaining legs filiform and weak ; the second and 

 third pairs didactyle, the fourth and fifth pairs monodactyle. Extreme length 9 lines: 

 arm and wrist united 6% lines ; hand 3 lines. The colour is straw (drying much dark- 

 er), dotted in some parts with pink and in others with orange. I caught this indivi- 

 dual on the 18th of August, 1852, in from 5 to 7 fathoms water, off Redcliffe Head, in 

 Weymouth Bay, on a bed of Cystoseira fibrosa. The most apparent difference be- 

 tween it and the adult Homarus vulgaris consists in the much shorter antennae, the 

 more slender and more equal anterior legs, the wider rostrum, and the more acutely 

 triangular plates of the segments. — William Thompson ; Weymouth, January 1, 1853. 



