ART. — 15. H. OHSHIMA I SOME OBSERVATIONS 



HistolOffy. 



The punctate or circular photophore is a hemispherical 

 cup-shaped epidermal swelling embedded in the cutis, while the 

 linear or elongate photophore is a semicylindrical body, which 

 may be regarded as being formed by coalescence of a number 

 of punctate photophores. The following description refers chiefly 

 to the punctate ones. 



The general features of the organ under the microscope 

 agree, on the whole, with the description given by Johann from 

 Spinax niger. 



One can find the following elements in each organ : 1) 

 involucre of pigment, 2) blood sinus, o) photogenic gland-cells, 

 4) " iris " with the pigment cells arranged in a ring, 5) 

 "Keimlager" and palisade cells, G) lens-cells. 



In paratangential sections through the organ, the photogenic 

 cells, about fourteen in number, appear radially arranged, while 

 in Sjnnax niger only from four to six of them have been stated to 

 be found. 



Around the orifice of the hemispherical body of photogenic 

 cells, a number of pigment cells are arranged in a circle, which 



