THE DEGENERATE EYES IN THE CUBAN CAVE 

 SHRIMP, PAL/EMONETES EIGENMANI HAY. 1 



FRANK H. PIKE. 



The blind shrimp whose eyes are considered in this paper is 

 common in the pools of the sink holes and caves near Canas on 

 the Western Railway of Cuba. The material was collected by 

 Professor C. H. Eigenmann, who described the localities in his 

 account of "The Fresh-water Fishes of Western Cuba" ('03). 

 The species was described by W. P. Hay, in his paper " On 

 a Small Collection of Crustaceans from the Island of Cuba" 



('03). 



Material. Four specimens were available for study. The 



general topographic relations were determined from a surface 

 study of the different specimens. The histological detail was 

 worked out mainly from one series of sections. The normal 

 marine shrimp from Wareham, Mass., was used for com- 

 parison. 



Methods. The animals were killed in formalin and transferred 

 to seventy per cent, alcohol. Preparatory to sectioning, the head 

 was cut off and placed in Perenyi's fluid for about twenty-four 

 hours, dehydrated, cleared in xylol, and imbedded in paraffin. 

 Longitudinal horizontal sections were made. They were mounted 

 on the slide by the water method, and stained with haemalum 

 and eosin. One specimen was killed in Vom Rath's fluid and 

 stained with safranin. The eyes of the normal shrimp were 

 depigmented by being placed in a ten per cent, solution of nitric 

 acid for from twenty-four to seventy-two hours before being 

 placed in Perenyi's fluid. The remainder of the technique was 

 the same as for the degenerate eye. 



1 Contributions from the Zoological Laboratory of Indiana University, No. 58- 

 This study was completed many months ago. Its publication has been delayed to 

 secure good photographs of the critical sections. The material was collected with a 

 grant from the Carnegie Institution. 



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