JOURNAL OF ENTOMOLOGY AND ZOOLOGY 73 



2. The brain Is chiefly made up of the optic and antennal lobes; 

 these are fused at the central portion of the brain with the lobes 

 of the antennules. There Is but'a short portion of the brain fused 

 from side to side. 



3. Although there are connections from the brain to the lower 

 levels these are not great because the connectives are narrow. 



4. With the exception of the rather complex optic lobes the 

 nervous system is of simple structure. There are no complex 

 masses of tangled fibers and fibrils. 



5. Cells sheath or accompany almost all parts of the central 

 nervous system. They are also massed in projecting lobes or 

 "neural crests" in the thoracic region, where they project caudally 

 and towards the middle line. 



6. A central cavity Is formed In the central region of the brain 

 where the two lateral halves are united only by a line of cells on 

 the dorsal surface. 



7. In spite of the fact that the animals are mature as deter- 

 mined by the germ cells, the nerve cells and nervous system seemed 

 almost embryonic. The masses of cells In places seemed only 

 slightly different from the body cells. 



REFERENCES 

 Claus, C. 1872 



Ueber den Bau und die systematische Stellung von Nebalia. 

 Zeit. Wiss. Zool. Bd. XXII. 



l: 



Ueber den Organismus der Nebaliden und die systematische Stel- 

 lung der Leptostraken. Arb. Zool. Inst. Wien Bd. VIII. 

 Lankester, E. R. 1909 



A treatise on Zoology, Part VIII, pp. 151-161. 

 Packard, A. S., Jr. 1883 



Monograph of the philopod Crustacea of North America with 

 remarks on the order Phyllocardia. 12th an. rep. U. S. Geo. Sur. 

 Ter. pp. 433-443. 



(Contribution from the Zoological Laboratory of Pomona College) 



