112 On the Organization of the Ctjprides. 



efferent duct passing towards the antennae commences near 

 the terminal saccule and is exceedingly difficult to trace. 



I'he maxillary gland is situated ventrally to the shell- 

 muscle and appears to consist principally of the terminal 

 saccule divided into several diverticula, from which the 

 efferent duct runs into the shaft of the maxilliped (second 

 maxilla). Besides these excretory organs, characteristic of 

 the Crustacea and representing the nephridia of the Annelida, 

 there are two glands in the labrum, and further some very 

 large gland-like cells in the basal joints of the limbs, and also 

 under the back, and particularly numerous within the cara- 

 pace attached to the hypodermis of the inner lamella. 



6. Sexual apparatus. — Like the copulatory apparatus of the 

 males of Cypridina and Halocypris the complicated penis of 

 the Cytherides and Oyprides represents a transformed (8) 

 pair of limbs. But the external sexual parts of the female 

 (still erroneously characterized as the vagina)^ which are 

 arched like a capsule, perforated by the sexual aperture, and 

 sometimes furnished with leg-like appendages, are also prob- 

 ably to be interpreted as the basal joints of a pair of limbs, 

 while the two abdominal appendages, which still constantly 

 figure as " Rami abdominales '' (caudal rami) or as caudal 

 spines, as also the so-called " postabdomen " of the Cypridinaa 

 and Halocyprides, represent the Uyo furcal joints of the Ento- 

 mostracan body. 



The long, fissure-like, sexual aperture, which is surrounded 

 by a chitinous band, receives the oviduct in its posterior sec- 

 tion, which is susceptible of dilatation by the action of powerful 

 muscles ; and the oviduct runs with many convolutions by the 

 sides of the intestine, and by means of its glandular ej)ithelium 

 secretes the shell-membranes of the contained ova in the same 

 way as the ovarian tube of the Insecta. The genital cleft in 

 its anterior angle, where it is dilated, surrounds the aperture 

 for the reception of the seminal filaments, which are of pecu- 

 liar form and enclosed by a chitinous loop. A complicated 

 apparatus follows on this copulatory aperture (which is dila- 

 table by a special group of muscles), and consists in the first 

 place of a saccule formed by a chitinous wall, then of a much 

 convoluted glandular tube and a chitinous tube originating 

 from the saccule, leading into the duct of the receptaculum, 

 which is spirally twisted like a watch-spring. 



