Miscellaneous. 193 



MISCELLANEOUS. 



On the Reproductive Apparatus of the Ephemeridae. 

 By M. Jolt. 



Male Genital Apparatus. — So far as we know, since Swammer- 

 dam, no one has studied the internal structure of the genital ap- 

 paratus of the Ephemeridae. Leon Dufour confesses his almost 

 complete ignorance on the subject of this apparatus *. F. J. Pictet 

 says nothing about it, or, at least, he speaks only of the external 

 organs assisting in copulation. The K,ev. A. E. Eaton, in his mo- 

 nograph t does not say a single word about the internal genital 

 organs. 



We regret that we have been unable to multiply our dissections 

 sufficiently to leave no important gap in our anatomical investigation. 

 We have sought in vain for the male organs in a great number of 

 individuals of that sex belonging to Palingenia virgo, which flew 

 about in the evening in the light of the lamps along the quays of the 

 Garonne +. It is probable that in them these organs were already 

 shrivelled up immediately after the accomplishment of fecundation. 



But in the males of Baetis sulphurea, which we liave several times 

 dissected, we have very clearly seen the internal genital apparatus, 

 formed of two testes, or milts as Swammerdam calls them §, placed 

 one on each side of the digestive tube. 



They present the form of two elongated, clavate sacs, recurved 

 into a hook at their apex, pure white, and with gibbosities on their 

 surface. The membrane forming their outer envelope is of extreme 

 delicacy, and contains large^., vesicles or spermatic capsules (cellules- 

 mires, Godard ; ogufs males, C. Robin), which in their turn are filled 

 with rounded spermogenous cells (cellules-JiUes, Godard ; celluhs em- 

 hryonnaires males, C. Robin), in many of which we have distinctly 

 seen the spermatozoids rolled upon themselves just like minute 

 snakes. 



The testicular tube or sac is bordered along its inner side by a duct, 

 to which the spermatic capsules appear to be suspended by a short 

 pedicle, like grapes to their stalks ; they thus open to the deferent 

 duct, which in its turn is continued into an ejaculatory duct which 

 penetrates into one of the two corresponding penises, traverses its 

 whole length, and terminates at the exterior orifice to pour out its 

 contents there. I say one of the two penises, because, by an excep- 



* " Recherches anatomiques et physiologiques sur les Orthopteres, lea 

 Hym^nopteres, et les N^vropteres, M(5m. des Savants Strangers, tome vii. 

 (1841) p. 581. 



t "A Monograph of Ephemeridae," in Trans. Ent. Soc. Lond. 1871, pp. 

 41-44 and 49-53. 



X In this species the males have always appeared to us to be much fewer 

 than the females. 



§ Swammerdam believed that the ova of the Ephemerae are fecundated 

 after the manner of those of fishes — that is to say, without previous copu- 

 lation. 



