SYSTEMATIC ACCOUNT 157 



(Text-fig. 6d). Some of the specimens are of full size; it therefore seems reasonable to assume that 

 this is the normal condition in non-breeding females of this species. The wide band of unchitinized 

 integument indicates that the development of these plates proceeds as an inward extension of the 

 coxae and lends support to the view, expressed elsewhere (Sheppard, 1939), that the plates are coxal 

 in origin. 



In the fully developed brood pouch in E. oculata only the distal inner half of each plate is free; the 

 outer parts are all connected together by the ventral integument, which, at about the middle of the 

 plate, becomes pushed up dorsally to form a large pouch, almost entirely filling the thoracic region of 



Text-fig. 7. Edotia oculata. {a) Brood pouch from above, dorsal integument removed (diagrammatic), a.c. accessory- coxal 

 plate; a.o. anterior opening of brood pouch; Cj, coxa of first pereiopod; c.p^, coxal plate of first pereiopod, unfused; c.p.., 

 coxal plate of second pereiopod, fused; c.p.^, coxal plate of fourth pereiopod, unfused; d, diverticulum of brood pouch; 

 ex, soft extension of coxal plate; /.c./>. free part of coxal plate; f.p. fold of posterior wall of brood pouch; /, limit of brood 



pouch ; Ip. hne showing displacement of ventral integument, dorsally and laterally, {b) Base of left 



maxiUiped to show coxal lobe, c.I. (c) Longitudinal section through brood pouch (diagrammatic), al. alimentary canal; 

 c.p. coxal plate; d, diverticulum of brood pouch;/./), fold of posterior wall of brood pouch; n.c. nerve cord; v.i. ventral 

 integument. Chitinous areas stippled. 



the body (Text-fig. 66). The free inner margins of the coxal plates (Text-fig. -ja) are produced into 

 membranous extensions; the posterior margins of the first three pairs of plates form large lobes 

 which overlie the plates immediately behind. The extensions of the inner margins are narrow and 

 curved upwards and overlap one another, alternately left over right, and right over left; in the text- 

 figure the plates are slightly pulled apart in the mid-ventral line. The inner edges of the main part of 

 the plates bear microscopic projections, while those of the last two pairs, in addition, are fringed with 

 setae, the whole forming an interlocking device. Thus, a firm ventral wall to the pouch is formed from 

 the distal ends of the coxal (brood) plates. The area of the ventral integument primarily involved in 

 the formation of the rest of the pouch is limited to the region between the free portions of the coxal 

 plates ; it extends from just in front of the first pair of plates to the posterior border of the fourth pair. 

 It has become greatly increased in size and is pushed dorsally towards the terga, carrying with it the 



