CRUSTACEA. 677 
Pinnoteres LAtR. Shell orbiculate. Peduncles of eyes short. 
Chele short, thick. 
Sp. Pinnoteres pisum LTR, (and Pinn. mytilorum ejusd.), Cancer pisum L., 
Fasr., Baster Natuurk. Vitsp. u. Tab. tv. figs. 1, 2, Cuv. R. Ant., éd. ill., 
Crust. Pl. 19, fig. 1, Bewn Brit. Crust. p. 121; in mussels, Another 
species, Pinnoteres veterum Bosc, lives in Pinna and was supposed by the 
ancients to warn this bivalve against impending danger (see C1cERO de 
Finib. mal. et bon, 1. Cap. 29, the mid.). 
The females are larger, have a broader shell and especially a much 
broader tail than the males. 
Sub-genera: Xanthasia, Pinnixa WuitE, Ann. of nat. Hist. Xvi. 
pp. 176, 177. 
Grapsus LAM. Shell depressed, subquadrate, with frons broad 
and lateral margins almost straight. yes placed at the lateral 
angles of shell upon short thick peduncles. Middle antenne hori- 
zontal, concealed under the reflected frons. First pair of feet short. 
Sp. Grapsus pictus LatrR., Cancer grapsus L., Desmar. Crust. Pl. 16, fig. 1, 
Cuv. R. Ani., éd. ill., Crust. Pl. 22;—Grapsus variegatus LatR., Canc. 
varieg. FABR., GUERIN Jconogr., Crust. Pl. 6, fig. 1. 
Add genera: Sesarma Epw. (Pachysoma Dr Haan), Varuna 
Epw. (Zrichopus Dn Haan), Pseudograpsus Epw. and some others, 
which must be here omitted. 
Gecarcinus Leach. Shell cordate, anteriorly broader, turgid, 
posteriorly truncated. Peduncles of eyes short, received in rounded 
furrows. 
Sp. Gecarcinus ruricola, Cancer ruricola L., DEsMAR. Crust. Pl. 12, fig. 2, 
&ec.; from 8. America. 
This genus contains the so-called land-crabs, that live in woods. Some 
betake themselves at a certain time of the year to the sea to lay their eggs, 
and undertake the journey in large troops, as travellers relate, in a straight 
line, from which they cannot be turned by any opposition. 
Plagusia LAtr. Frons excised on both sides for middle an- 
tenn denuded above, porrect. Shell broad, narrowed anteriorly. 
First pair of feet short. 
Sp. Plagusia clavimana, Desmar. Crust. Pl. 14, fig. 2, &e. 
Ocypode Fapr. Shell quadrate or trapeziform, anteriorly 
broader. Middle antenne short, with two very small sete; lateral 
antenne small. Eyes placed on long peduncles. Chela in males 
_ often very large on one side, far surpassing the chela of the other 
side. 
