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THE OENOCYTES 



The name oenocytes was given by Wielowiejsky (1886) to 

 certain large wine-colored cells observed embedded in the fat body 

 of the larvae of Corethra, and which he also found in other 

 insects belonging to several different orders. 



This investigator was, however, not the first to note these cells, 

 for as Graber (1891) has stated, similar cells had been previously 

 observed and described by other investigators, as for example, 

 by Tichomiroff (1882), in the embryos of the silk worm. After 

 Wielowiejsky called attention to the oenocytes they were observed 

 in the larvae and imagoes of insects belonging to so many different 

 orders that they are now generally assumed to be common to all 

 pterygote insects. They differ much in different orders ; the prin- 

 cipal features which they have in common appear to be their 

 relatively large size and their ectodermal origin. To this it may 

 be added that after leaving the ectoderm they have never been 

 seen to divide. They are always found more or less closely 

 associated with the cells of the fat body, and often attached to 

 tracheae. They may be scattered or arranged in clusters, in which 

 case a pair of clusters is usually situated in each of the first eight 

 abdominal segments, as in Corethra. Little is known of the func- 

 tions of the oenocytes, although several attempts have been made 

 to solve this problem, the latest being that of Glaser (1912), who 

 has studied the oenocytes of the larvae of the leopard moth and 

 finds evidence that they contain oxydising enzymes. 



The development of the oenocytes has been observed by several 

 investigators. Graber (1891) calls attention to the fact, that prior 

 to the appearance of Wielowiejsky's paper, Tichomiroff (1882) 

 and Korotneff (1885) had described the development of cells to 

 be regarded as identical with oenocytes, and that later Heider 

 (1889) had also observed an ectodermal proliferation which was 

 probably concerned in the development of oenocytes, but without 

 recognizing its significance. Graber also described the develop- 



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