ON THB DEVELOPMENT OF NEBALIA. 429 



Reichenbach, H. — 1SS6. ' Studien zur Entwicklungsgeschichte des Pluss- 

 krebses.' 



Sars, G. 0. — ]SS5. 'Clialleuger Reports,' vol. xiii. 



1887. ' Clialleuger Reports,' vol. xix. 



Thomson, G. — 1894. "On a Freshwater Scliizopod from Tasmania," 'Trans. 

 Linn. Soc.,' London. 



ViALLANES, H. — 1892. " Systeme nerveux des Articules." 'Annales des 

 Sciences naturelles,' 7e serie, Zoologie, 13, 14. 



V. WiLLEMOES-SuHM, R. — 1875. "On some Atlantic Crustacea from the 

 ' Challenger' Expedition." 'Trans. Linn. Soc ,' London, ser. 2, Zool., 

 vol. i. 



Wagner, Jul. — 1894. "Zur Entwicklungsgeschichte der Schizopodon," 

 ' Zoologiscber Anz.,' Bd. xvii, p. 437. 



EXPLANATION OF PLATES 16— 2L 



Illustrating Miss M. Robinson's paper " On the Development 



of Nebalia." 



Eeference Letters. 



aui. Antenna, a.ff. Antennary gland, a.p. Abdominal papilla, bd. 

 Blastoderm, bp. Blastopore, cut. Cuticle, c.ff. Caudal groove, e.c. 

 Crystalline cone cells. c.i. Caudal thickening, cm. Central mass of 

 nervous tissue, d. Depression in optic thickenings, div. Dividing cells. 

 dc. Deuterocerebrum. ec. Ectoderm, en. Endoderm. _/. Fold between 

 shell thickening and body wall. ff.c. Genital cells, ff. Ganglion, k.c. 

 Heart cells, kep. Hepatic lobes, k./. Head flap. I.e. Large cells of the 

 ectoderm, lab. Labrum. m. Mouth, md. Mandible, war. Maxilla, mes. 

 Mesoderm, mus. Muscle, n./. Nerve fibres, o.i. Optic thickening, op.in. 

 Optic invagination. o.l. Optic lobe. pc. Protocerebrum. p.u. " Pale 

 nuclei" of the optic invagination, proc. Proctodeeum. s. Shell, si. 

 Stomodseum. s.v. Shell valve, ic. Tritocerebrum. vp. Vitellophag. wed. 

 Wedge-shaped cells, y. Yolk. y.s. Yolk sac. 



Exigencies of space have forbidden the drawing of more than the ventral 

 half of each section in most cases. 



The magnification of the sections is 475, except where otherwise stated. 



