40 



THE DEVELOPMENT OF 



'84, Urbanovvicz, Felix. — Zur Entwicklungsgeschichte der Cyclopiden. 



Zool. Anz., VII, pp. 615-619. 1884. 

 '78, Whitman, C. O.— The Ernbryology of Clepsine. Quarterly Jour. 



Micros, Sei., xviii, pls. xii-xv. July, 1878. 

 '86 (Whitman, C. O.). The germ layers of Clepsine. Zoöl. Anz., ix, 



pp. 171-176, 1886. 

 '87, A contribution to the history of the germ-layers in Clepsine. 



Jour. Morphol., i, 105-182, pls. iv-vi. 1887. 

 '87, Wilson, E. B. — The germ-bands of Lumbricus. Journ. Morphol. 



I, pp. 183-192, pl. VII. 1887. 



EXPLANATION OF PLATES I, II AND III. 



The numbering of the figures is consecutive with that of the pre- 

 cediug part (Vol. xviii, pls. i and ii). 



REFERENCE LETTERS. 



a abdomen. 



af abdominal flexure. 



an an US. 



ap appendage. 



hc body cavity. 



hg boundary between optic 

 and cerebral ganglia. 



hl blastopore. 



c cerebral ganglion. 



CG crystalline coue. 



ch chorion. 



cl corneal lens. 



cm commissure or commis- 

 sural fibres. 



CO body cavity. 



et cuticle. 



cv connective or connective 

 fibres. 



d dorsal vessel. 



dm dorsal mesoderm. 



do dorsal organ. 



e ectoderm. 



ec edge of carapax. 



eo external opening of green 

 gl and. 



ex exteiisor muscles of ab- 

 domen. 



ey 



eye. 



f 



flexor muscles of abdo- 





men. 



/c 



fibres of cerebral gang- 





lion. 



fo 



fibres of optic ganglion. 



^(1 



-17) ganglia of the primi- 





tively postoral series. 



ga 



germinal area. 



gc 



germinal cells. 



gg 



green gland. 



gm 



stomacli. 



gt 



gastric teeth. 



h 



entoderm. 



ht 



heart. 



i-xx 



appendagcs. 



i 



iutestiue. 



l 



labrum. 



li 



*' liver." 



m 



mesoderm (mouth in flg. 





11). 



me 



mesentery. 



gm 



mesoderm of green 





gland. 



mn 



mandibular nerve. 



mo 



mouth. 



mu 



nmscle. 



