3o6 



A. TEKAO : 



Acanthephyra debilis, in which, according to Kemp, it should be permeated 

 by a deep violet-blue coloring matter. 



The lens, when viewed surface on, is either circular or oval in outline, 

 the diameter varying from 45 fi to 143 yu in the former case and from 

 41 x 32 fi to 169 x 150// in the latter. Roughly speaking, the size increases 

 as the individuals grow older and larger, as will be seen from the following 

 table : 



Sex 





K 







Total length of body 



29 mm 



34 mm 



39 mm 



43 mm 



Carapace length 



7.5 mm 



8.5 mm 



10.5 mm 



12 mm 



Median photophore of 1st abdominal 

 sternite 



I31X92 |A 



135X9811. 



169X 150 \i 



154X 128 n 



Median photophore of 4th abdominal 

 sternite 



105X IOI JJ. 



1 1 3 X 1 09 <J. 



143X143 V- 



154X135!* 



3rd photophore of 6th abdominal 

 sternite 



83X71 



98X79 



107x87 |X 



98X92 [J. 



Proximal photophore of left exite 

 of uropod 



81X71 V- 



113X94 |J- 



116X98 (i. 



120 X 99 [J. 



Distal photophore of same 



45x45 



71 X68 y. 



90x83 |i 



83X75 H 



2) The lens epitlieliunt. — Since the lens is but a local thickening 

 of the cuticula, it is quite natural that there exists directly beneath it a 

 cellular layer continuous with, and similarly charaterized as, the hypodermis 

 of the general body surface. The latter (fig. 1 , hy) is an exceedingly thin 

 epithelium, in which the cells are indicated mainly by their flattened nuclei 

 arranged in a single layer and all pressed flatly against the cuticula. Now, 

 that part of the hypodermis which lines the inner convex surface of the lens 

 may be distinguished by the designation of lens epithelium (/e). Hansen 

 seems to have observed this in .S". cliallcngeri, without however coming into 

 definite knowledge of its nature nor even of its real existence. Kemp has 

 entirely overlooked the epithelium in the same species, though the nuclei 



