49, JOURNAL OF ENTOMOLOGY AND ZOOLOGY 
(7) The connections of the small lateral ganglia are slightly 
different from those of most other insects so far described. 
(8) The ganglia are rather large as compared with the 
small size of the animal. 
(9) The nerve cells are very small, smaller than the nuclei 
of some other cells of the body. 
IwportTaNnT REFERENCES 
Becker, E. 1910 
Zum Bau des Postantenalorgans der Collembolen. Zeit. f. 
Wiss. Zool. Bd XCIV, Hefte 3. 
Boettger, O. 1910 
Das Gehirn eines neideren Insektes (Lepisma saccarina L.) 
Inag. Dis. Uniy. Jena. 
Grassi, B. 1889 
Anatomie comparee des Thysanoures, Arch. It. Biol. 
Philiptschenko, Jur. 1912 
Beitrage zur Kenntnis der Aptergoten. IIIT Die Embry- 
onalentwicklung von Isotoma cinerea Nic. Zeit. f. Wiss. Zool. 
Bd. CIII Heft 4. 
(Contribution from the Zoological Laboratory of Pomona College.) 
