DECAPODA. 61 



In one of them, the Scyllare ours; Cancer arctus, L.; Cigale de 

 mer, Rondel., livr. XIII, chap. VI j Herbst., XXX, 6, the ex- 

 ternal or lateral antennas are much dentated. The thorax is 

 marked with three longitudinal and dentated ridges, and the 

 superior surface of the tail sculptured, but its lateral margin 

 not crenulated. 



The other, Scyllarus sequinoxiuUs, Fab.; Scy Hants orientalis, 

 Risso; Squille large, or the Orchetta, Rondel.; Gesn., Hist, des 

 Anim., Ill, p. 1097, is large, shagreened, and without ridges. 

 The crests are edentated, and the margin of the segments of the 

 tail crenulated. Its flesh is highly esteemed and the ova are 

 of a vivid red. 



2. Thenus, where the fore part of the thorax is broader than it is 

 long, each lateral margin deeply incised, and the eyes are placed at 

 its anterior angles(l). 



3. Ibacus, only differing from Thenus in the position of the eyes, 

 which are approximated to the origin of the intermediate antennae. 



In an Australian species, Ibacus Pronii, Leach, Zool. Miscel., 

 CXIX; Desmar., Consid., XXX, 12, the exterior lateral mar- 

 gin of the third joint of the external foot-jaws is transversely 

 striated and notched in the manner of a crest(2). In the 



Palinurus, Fab. 



The lateral antennas are large, setaceous, and bristled with 

 spines. 



Of these Crustacea, called Carabos by the Greeks, and Locusta by 

 the Latins, and on which Aristotle made several important observa- 

 tions, some attain a length of nearly two metres, the antennas in- 

 cluded. The species found in European seas remains in deep water 

 during the winter, and only visits the coast on the return of spring. 

 Rocky localities are its favourite haunts. It subsequently deposits 

 its ova, which are of a beautiful red colour, whence their name of 

 Coral. At this period more males are taken than females, while 

 after the spawning season the latter are most abundant. According 

 to Risso a second copulation, followed by another production of ova, 

 takes place in the month of August. The Palinuri are disseminated 

 throughout all the seas of the temperate and intertropical zones, but 

 are particularly abundant in the latter. Their shell is rough, covered 



(1) Thenus indicus, Leach; Scyllarus orientalis, Fab.; Rumpli., Mus., II, D.; 

 Herbst., XXX, 1; Encyc, Atl. d'Hist. Nat, CCCXIV; Desmar., Consid., XXXI, 1. 



(2) Add Scyllarus antarcticus; Fabr., Herbst., xxx, 2, Rumph., Mus., IT, D. 

 See the article Scyllare, Encyc. Methodique. 



