312 CRUSTACEA. 



FAMILY II. MACROPHTHALMID,E. 



THE Macrophthalmidae are remarkable for the length of their eye- 

 peduncles; for their trapezial or quadrate form, the anterior angles 

 being prominent, and the breadth of the carapax generally greatest 

 between them; and for having the male abdomen much narrower 

 behind than the contiguous part of the sternum. The species of 

 Grapsidae which approach most to the Macrophthalmidoa have a ridge 

 (usually piliferous), crossing obliquely the third joint of the outer 

 maxillipeds, and may thus be distinguished, as this character belongs 

 to no true Macrophthalmidae. 



In the genera of this family, the outer maxillipeds are wholly ex- 

 posed, excepting in a small group, in which the extremity is concealed 

 beneath the broader basal portion. And among those having these 

 maxillipeds of the normal character, part have the inner antenna? 

 transverse, and part longitudinal. There are thus three distinct sub- 

 families in this family. Their characters and the distinctions of the 

 genera they contain, are as follows : 



SUBFAM. 1. MACROPHTHALMIN^E. Antennae internoe transversoe, 

 sub fronte insitae. Antennae externae basi frontem appressac. Ar- 

 ticulus maxillipedis externi 4tus apertus. 



Gr. 1. CLEISTOSTOMA, De H* Carapax subquadratus, paulo transversus. . Frons 

 quarta parte latitudinis carapacis vix brevior. Oculi longiusculi. Pedes antici 

 maris feminseve breves. Articulus maxillipedis externi Stius 2do vix minor, 

 quadratus. 



G. 2. MACROPHTHALMUS, Latr. Carapax latus, transversim rectangulatus. 

 Frons angustissimus. Oculi longissimi. Artieulus maxillipedis externi Stius 

 2do multo minor. 



SUBFAM. 2. OCYPODINJ3. Antennae internae longitudinales, juxta 

 frontem utrinque insitae. Antennae externse fronte paulum reniotae. 

 Articulus maxillipedis externi 4tus apertus, Stius 2do minor. 







1. Articulus maxillipedis externi 2dus Stio valde major. 

 G. 1. GELASIMUS, Latr. Oculi graciles, cornea parvula, parce oblonga. Pedes 



* Crust., Faun. Japon., p. 26. From xXEiaVoj, shut, and rfro(j.a, mouth not Cleis- 

 totoma. 



