of the Ova o/'Chtlionius. 



199 



of the ovary is pushed outwards in the form of a round emi- 

 nence, giving rise to the peculiar racemose form of tlie ovary. 

 As the deveIoj)nu'nt of the ova advances, the wall of the ovary 

 is nushed still more outwards, so that then each ovum is 

 enclosed in a perfectly homogeneous follicle* (therefore with- 

 out any ei>ithelial layer), the basal section of which appears 

 in the form of a short pedicle lined with nucleated cells 

 arranged in a spindle-like form. 



Embrvonal development in Chthoniux, represented iu seven successive 

 stajres : i/,, blastoderm (first kyer) ; hh, mesoderniic cells (?);/", 

 follicle ; «/, coarser jrranulesof the protoplasm ; h, Purkinje's vfsicle ; 

 AA, vitelline membrane; p, protoplasm; jxl, primary deutoplasm- 

 spiieres; kiu, secondary membrane; sd, secondary deutopla^m-spheres 

 (mitritive vitellusj. 



The ovum is now developed chiefly by a rapid increase of 

 volimie of the proto])lasm, in which we must distinguish two 

 kiufls of granules, coarser and finer. The coarser granules 



• Von Wittich, ' Observationes qujrdam de Aranearum ex ovo evolu- 

 tione,' I»is,s. inau2'. Hilis SaxonifP, 184-5; and id. "Die Ent^tehnnp des 

 Arachnideneiea iin Kierstnck, die ersten V'orgnnpe in demseiben nach 

 seineni Verla-ssen des Mutterkbrpers," Miiller's Arch, fiir Anat. und 

 Phvsiol. 1*449. pp. 112-1.50. pi. iii. (."leep. llfi). 



14* 



