Ah'acellaneous. 1 93 



MISCELLANEOUS. 



On the Reproductive Ap/>nratiis of the Ephemeridce. 

 By M. Jolt. 



Male Oenital Apparatus. — So far as wo know, siuco Swammer- 

 diitn, no one has stiuliod the internal structure of the genital ap- 

 paratus of the Ki»h('meridic. Leon Dufour confesses liis almost 

 complete iji^norance on the subject of this apparatus *. F. J. Pictet 

 says notlun;i; about it, or, at least, ho speaks only of the external 

 organs assisting in copulation. The Rev. 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. 

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

 individuals ot" that sex belonging to Paliiif/enia virgo, which flew 

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

 Garonne J. It is })robable that in them these organs were already 

 shrivelled up immediately after the accomplishment of fecundation. 



Eut in the males oi Bcietis sidj^hnrca, which we have several times 

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

 formed of two testes, or mills 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^t.vesicles or s^jermatic capstdes {celhdes- 

 mh'es, Godard ; ceufs males, C. Robin), which in their turn are filled 

 with rounded spermogenoii^ cells (celltdes-Jilles, Godard ; cdhdes emr- 

 bri/onnaires males, C. Robin), in many of which we have distinctly 

 seen the spermatozoids rolled upon themselves just like mijiute 

 snakes. 



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

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

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

 duct, which in its turn is continued into an ejaculatorj' duct which 

 penetrates into one of the two corresponding pouises, 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 lea Orthopteres, les 

 Hvm(<nopteres, ct les Ncvroptores,' M^m. des Savants etrangers, tome vii. 

 (1'841) p. 581. 



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

 41-44 and 40-.'5;?. 



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

 than the f(>raales. 



§ Swammerdani believed that the ova of the Ephemerae are fecundated 

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

 lation. 



