668 CLASS x. 



Compare LEACH On the characters of the genus Thalassina of LATREILLE, 

 Zool. Misc. in. 1817, pp. 27, 28. 



*f* Accessory branchial appendages cylindrical, dichotomous, adhering to 

 the abdominal feet. 



Callinidea EDW. 



Callinisea EDW., Isea GUERIN. 



Compare GUERIN Description d'un nouveau genre de crustace macroure. 

 Ann. de la Soc. entom. de France, I. 1832, pp. 295 300. 



1 1* External branchice none. 



a) Four anterior feet didactylous. 



Thalassina LATE, (in part), LEACH, Axius LEACH, Callianassa 

 LEACH. 



Sp. Thalassina scorpionides, Cancer anomalus HERBST, LEACH Zool. Misc. 

 Tab. 130, DESMAR. Crust. PL 35, fig. i, GUERIN Iconogr., Crust. PL 18, 

 fig. 4 ; from the coast of Chili ; Callianassa subterranea LEACH, DESMAR. 

 Crust. PL 36, fig. 2, GUERIN Iconogr., Crust. PI. 19, fig. 4, on some parts 

 of the English coast and in the Mediterranean. According to EDWARDS 

 Callian. laticauda OTTO, Nov. Act. Acad. Cces. Lcop. Car. Tom. xiv. 

 Tab. 21, fig. 3, is not specifically different from it. 



b) Two anterior feet alone didactylous. 



Genera : Gebia LEACH and Glaucothoe EDW. (Prophylax LATR. ?) 



Note. Genus Megalopa LEACH, Megalops EDW., placed here by 

 LATREILLE between Galathea and the preceding genera, must be 

 suppressed; from the observations of THOMPSON and RATHKE it 

 belongs to the earlier forms of brachyurous Decapods. The same 

 conclusion is to be formed respecting Monolepis SAV. 



THOMPSON Phil. Trans. 1835, PP- 358 362, PI. v. ; RATHKE Beitr. z. 

 Vergl. Anat. 1842, p. 46. 



Galathea FABR. Middle antennas short, geniculate, terminated 

 at the apex by two setae ; external long, with elongate, multiarticu- 

 late seta, without a scale at the^base. First pair of feet large, 

 chelate ; fifth pair of feet slender, recurved. Shell ovate, depressed. 



Galathea and Grimothea LEACH. 



Sp. Galathea strigosa FABR., Cancer strigosus L., DESM. Crust. PL 33, fig. i, 

 GUERIN Iconogr., Crust. PL 17, fig. 3. 



