208 



Fig. G9. Longitudinal section through the eye. The 



optic ganglion is also shown. x 12. 

 Fig. TO. Enlarged drawing of two of the omniatidia 



from the previous figure. x 450. 

 Fig. 71. Transverse section across one of the omniatidia 



in the previous figure, through the rhabdome 



and retinulae. x 1000. 



Fig. 72. Transverse section across one of the omniatidia 

 in the previous figure, through the vitrella and 

 the pigment cells. x 1000. 



Fig. 73. Surface view of the cornea, showing one of the 

 corneal facets, x 750. 



Fig. 74. Olfactory seta taken from the exopodite of the 

 first antenna. x 1100. 



Fig. 75. Auditory seta (" hooked seta ") from the audi- 

 tory sac of the first antenna, x 400. 



Fig. 7G. Auditory seta (" group seta ") from the auditory 

 sac of the first antenna. x 800. 



PLATE XII. 



Fig. 77. Reproductive system of a fairly mature female, 

 showing the double ovary, the spermathecae 

 and the oviducts. x 1. 



Fig. 78. Reproductive system of an immature male, 

 showing the paired testes, the vas deferens and 

 the ejaculatory duct. The fore-gut is also 

 shown in position. x 2. 



Fig. 79. Section through an almost ripe ovary, showing 

 the eggs filled with yolk granules. The 

 details are only inserted in one egg. x 190. 



Fig. 80. A very early stage in the development of the 

 embryo, attached to a seta of an endopodite 

 of a female pleopod. This drawing shows the 

 method of attachment. x 50. 



Fig. 81. Ripe spermatozoon, showing the two processes. 



Taken from spermatheca of female, x 1400. 

 Fig. 82. Some of the epithelial cells of the bladder of the 



excretory system. The striated nature of the 



protoplasm is shown, x 650. 



