Lt T BBOCK ON SPHJEKULAEIA. BOMBI. 53 



MALE. 



All the specimens met with by V. Siebold, and all the large ones which 

 I have seen, were females. I observed, however, in the second specimen 

 which came under my notice, that there was a small nematoid worm at- 

 tached to the large female, PI. 1,/. 1, A, near to the end in which lies the 

 free extremity of the ovary. This minute worm was apparently overlooked 

 both by LeonDufour and Y. Siebold ; or, if they saw it at all, they proba- 

 bly mistook it for one of the ordinary young ones. It is always, how- 

 ever, in very close connexion with the female, the skins of the two being 

 firmly attached to one another; and, if the small worm is torn away, there 

 is a sort of rent at the spot where the attachment takes place. On the 

 other hand, we know that in many nematoid worms the male is much 

 smaller than the female, and the two are, during copulation, closely con- 

 nected together; in Syngamus trachealis, indeed, this is so much the 

 case, that the pair have been mistaken for a single animal. Moreover, 

 although the small attached worm in Sphserularia is not altogether ex- 

 actly like the ordinary young ones, still, in size and general appearance, 

 it remarkably resembles them ; and, lastly, unless we may regard it as 

 being the male, that sex is, as yet, entirely unknown. Although, there- 

 fore, I have not been able to distinguish any generative organs, or trace 

 of spermatozoa, I think that I am justified in considering that in Sphoe- 

 rularia the male is far smaller than the female, and that the two are 

 fastened together in a certain definite manner and position. The shape 

 of tail is also quite different from that of the larva ; in PI. 1, /. 6, I have 

 represented one of the young worms ; and in /. 7, one of the attached 

 specimens ; and it will be seen that the tail is quite dissimilar, being 

 straighter, and more pointed in the latter. Of what nature, then, is this 

 minute worm, and what are its relations to the large female Sphaerularia ? 

 Three possibilities only occur to me, viz. : that it might be the larva, a 

 parasite, or the male. 



There is, however, no instance in the Nematoidea of any such mode 

 of metamorphosis; and the little creature, though quite motionless, looks 

 too fresh and transparent to be merely the shrivelled-up skin of the 

 young. The difference of shape just alluded to, also, militates against 

 this view, which is, I think, quite untenable. 



Nor is the parasitism of the little creature a more probable supposition. 

 In the first place, the almost, if not quite, invariable presence of the 

 little worm speaks against it ; and, secondly, the mode of its attachment 

 is almost equally conclusive, as no Nematoid worms are external para- 

 sites.* Moreover, it is evident that this little worm must perish at the 

 same time as, or soon after, the Sphoerularia, and it is equally clear that 

 in the month of July this latter has not long to live ; if, therefore, the 



* It might, however, be said, that as this law arises from the necessity that the ex- 

 ternal surface should be bathed by animal fluids, the present case might be an exception 

 caused by the fact that the little worm, though external to the female Spha&rularia, was 

 internal as regards the Bee. 



