334 Mr. Newport on the Natural History 



Xenos sphecidarum, and which, like previous observers, he then thought were 

 parasites, but he also discovered and described the ova in whicli they were pro- 

 duced within the body of the Xenos. More recently * he has shown that these 

 are the ova and the young oi Xenos ; and that the female Strepsiptera are blind, 

 apodal, larviform insects, that never leave the bodies of the Hymenoptera in 

 which they have lived as parasites, but remain with only the cephalo-thoracic 

 portion of their bodies exposed, and there produce their young and die. The 

 males escape, and fly abroad as winged insects, and impregnate the females 

 while these are still within the Hymenoptera in which they have been nou- 

 rished. The larvae, consequently, as in Hippobosca, Aphis, and some other of 

 the inferior parasitic tribes, are hatched within the bodies of their parents, 

 and pass out, to the surface of that of the wasp or bee, through the vulva, 

 which is situated in her cephalo-thorax on the ventral surface. The larvae 

 thus produced (Tab. XIV. fig. 21), like those of Meloe, are at first distinctly 

 hexapod, and capable of locomotion ; they cling fast to the hairs on the body 

 of the wasp or bee (Tab. XIV. fig. 22) in which they have been hatched, and 

 are transported by the insect to its nest, where they remain, as I have already 

 shown is the case with Meloe. The larvae of Strepsiptera penetrate the body 

 of the young larva of the hymenopterous insect in its cell, and locating them- 

 selves in it, shed their skins, lose their legs, become completely apodal, and 

 there feed on its substance, through the whole period of their nutrition, as 

 internal parasites. These facts have been fully exemplified by Dr. Sieboldf. 

 The attention of naturalists was drawn to them quickly after their publication, 

 in France, by MM. Milne Edwards;}: and Guerin Meneville §, and in this 

 country by myself |1, my friend Mr. Spence having kindly apprised me of 

 them. Since then, some of them have been confirmed by Mr. Smith's^ and 

 my own observations. I have detailed Dr. Siebold's discoveries here, in their 

 natural sequence, in order, first, more fully to confirm them, and to add some- 

 thing to the description and history of these singular insects ; and next, to be 

 enabled more readily to compare the anatomy and habits of the larvae with 

 those of Meloe. 



* Wiegmann's Archiv, 1843. t If>id- P- 137 et seq. 



t Ann. des Sci. Nat. 1844. § Rev. ZooL, March 1844, p. 111-118. 



II Anniversary Address Ent. Soc. Lond., Feb. 1845, pp. 19, 20. 



% Zoologist, No. xxiii., Sept. 1845, p. 1092. 



