206 HEMENWA V. [VOL. I. 



sections, the fourth having been pushed out. The nuclei of 

 the retinular cells lie in the distal portion. The pigmentation 

 of the eye consists partly of the pigment granules in the retin- 

 ular cells and partly in the separate pigment cells. Of the 

 latter there are three distinct groups : (i) a circle of from 

 eight to ten large flattened cells, the outer tier of my descrip- 

 tion around the outer part of the crystalline body ; (2) long, 

 spindle-shaped pigment cells situated between the ommatidia, 

 extending to the inner cuticula ; (3) a third group, the supple- 

 mentary cells of my account, is found on the posterior part of 

 the retinula, between the retinular cells. 



Grenacher also mentions the pigmentation of the optic nerve 

 and the " inner cuticula." 



Adensamer ('93), in his studies on this eye (Scutigera coleop- 

 trata), confirms and completes Grenacher's statements. He 

 differs in certain points. 



The cornea of each ommatidium Grenacher regarded as 

 externally convex, although there were individual differences. 

 These differences Adensamer regards as stages in the develop- 

 ment of the cornea. 



In the adult eye frequently there were found in the crystal- 

 line body large yellowish enclosures, which had the appearance 

 of fat drops. These are not to be confused with the nuclei 

 for which Grenacher looked. Of the segments he found from 

 seven to nine. 



But in an individual 5 cm. long Adensamer states that he 

 found nuclei in the crystalline body ; thus he feels justified in 

 calling the segments " cells." 



As to the nerve fibers he was more successful than Grenacher, 

 in that he saw the connection of the fiber with the outer and 

 inner row of retinular cells. This he proved by sections. Just 

 under the basal membrane there is a nerve connected with a 

 muscle, which is entirely distinct from the optic nerve. Aden- 

 samer believes that this was probably mistaken by Grenacher for 

 the real optic nerve. The latter consists of a bundle formed of the 

 separate nerve fibers meeting proximal to the basal membrane. 



Speaking of the superficial resemblance of the eye of Scuti- 

 gera to that of insects and crustaceans, and the actual differ- 



