No. 3. — Simple Eyes in Arthropods. By EH. L. Marx.* 
Tat portion of Mr. Locy’s paper on the development of the spider t 
which deals with the formation of the eye appears to possess importance 
outside the objects of his special study. The discussion of the bearings 
of his discoveries on the simple or monomeniscous eyes of Arthropods in 
general, is the object of the present paper. 
Two irreconcilable views have been held of late with regard to the 
origin of the retina in the simple eyes of Arthropods. The writers upon 
the subject have been prettv evenly divided in oninion.  Grenacher 
Museum of Comparative Zodlogy, Cambridge, Mass. 
With the compliments of 
ALEXANDER AGASSIZ. 
— wea ee NS Ow eee A EEUU ALLUIiU ALL ULG SLUM 
rere) , page > 
hangigkeit des Retinaelementes, sondern auch aller iibrigen Augentheile 
von dem Integument, der Hypodermis mit Cuticula, erkennen lassen. 
Damit ist aber fiir diese Thiere auch zugleich die Abstammung des Reti- 
naelementes vom ersten, 4usseren embryonalen Keimblatt, dem Ectoderm, 
gegeben. 
“ Nicht so giinstig steht es mit den iibrigen Formen von Larvenaugen, 
sowie den einfachen Augen der Spinnen und Insectenimagines. Wenn 
* Contributions from the Zodlogical Laboratory of the Museum of Comparative 
Zodlogy at Harvard College. No. XI. 
+ Wm. A. Locy, Observations on the Development of Agelena nevia, Bull. Mus. 
Comp. Zodl., Vol. XII, No. 3, pp. 63-103, 12 pl., Jan., 1886. 
VOL. XIII. — NO. 3. 4 
