THE STRUCTURE AND SYSTEMATIC IMPORTANCE OF 

 THE SPERMATOPHORES OF CRICKETS. 



J. P. Jensen. 



In several groups of animals, we find that the spermatozoa 

 are held in packets or masses, and in some such as the Cephalo- 

 pods, there is high specialization of the spermatophore, as the 

 organ is called, in which the spermatozoa are contained. 

 Among the insects, only representatives of a few groups form 

 spermatophores, but when present they are beautiful and inter- 

 esting structures and those formed by the gryllids or crickets 

 are especially so. 



While engaged in research work on crickets in the Entomo- 

 logical Laboratory of Cornell University, I noticed one day that 

 a female Gryllus had a small pear-shaped organ attached 

 between the ventral surface of the base of the ovipositor and 

 the posterior end of the 8th abdominal sternite (Fig. 1). This 

 structure did not seem to be part of her own body and as I did 

 not at the time know anything about spermatophores, I was 

 very much puzzled by it. After investigating the literature I 

 found that I had happened to collect the specimen before the 

 spermatophore had dropped off, and upon examining several 

 males, I found a similar organ in situ in most of them, just out- 

 side of what was considered the genital opening and covered 

 by the ends of the posterior sclerites. 



Crickets, such as members of the genera Gryllus, Nemobius 

 and Oecanthus are very difficult to classify and I had encoun- 

 tered considerable difficulty in obtaining good specific charac- 

 ters. More with a view of determining whether the spermato- 

 phores might not assist me in classifying them, than expecting 

 to make any morphological discoveries, I commenced to study 

 them somewhat thoroughly. 



The literature was searched for accounts of copulation in 

 these and related insects and five references were found. Ser- 

 ville stated that in copulation the female Gryllus mounts the 

 body of the male, as in the Oecanthids. Peytoureau said that 

 in the Locustidae the transfer of spermatozoa takes place by 

 means of a pear-shaped spermatophore that is transferred to the 



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