NOTES ON THE MALE GENITAL SYSTEM IN CERTAIN 



LEPIDOPTERA.* 



By Herbert Ruckes, A. M. 

 INTRODUCTrON. 



Changes going on in organisms, whether studied grossly 

 or minutely, have always been interesting subjects and many 

 times astonishing truths have been revealed, where they were 

 least expected to occur. 



A great deal of the work carried on in entomological 

 histology, especially under the heading of metamorphosis, has 

 been relative to the muscular system, alimentary tract, adipose 

 tissue, etc., while little attention has been given to other equally 

 important systems. This is true of the reproductive system; 

 so for this reason a study of the morphological and histological 

 metamorphosis of the male genital tract in certain Lepidoptera 

 was attempted. 



The study was worked out under the direction of Professor 

 W. A. Riley, to whom the writer is indebted for his prolonged 

 patience and valuable criticism, and for the use of prepared 

 slides. The writer also wishes to thank Professor Lester W. 

 Sharp for his advices regarding the subject of spermatogenesis 

 and for the use of his slides of maturation mitosis in insects. 

 To Mr. John R. Eyer thanks are also due for use of his valuable 

 slides of the genitalia of a large number of Lepidoptera. 



The Lepidoptera were chosen to be worked on, for the meta- 

 morphosis could be readily controlled, by artificial means; and 

 besides, this group shows apparently a greater diversity in the 

 form of the genital system than most other orders. The 

 Saturniidae were chosen because when the study was first 

 begun, they were most abundant. 



Studies in the morphology and internal anatomy of insects 

 date back to the earliest zoologists. Dissection of forms, 

 however, did not properly commence till the advent of the 

 microscope, so that we find the first worker on the genital 

 system to be Malpighi (1669) whose treatise on the internal 



* Contribution from the Entomological Laboratory of Cornell University. 

 This paper is part of a thesis (by title. On the Metamorphosis of the Genital 

 System in the Saturniidae) presented as part requirement for the degree of Master 

 of Arts. 



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