10 



Mas differt, genis clypeoque albidis ; thorace, abdomine, squamaque alarum, 



nigris. 

 Habitat in Epiro rubis exsiccatis circum Ambracicum sinum. 



Sp. 2. Hylecs versicolor. 



Niger ; genis, clypei linea, protboracis linea interrupta, humeris, squamaque ala- 

 rum, flavescentibus ; an tennis subtus ferrugineis; tibiis tarsisque anterioribus 

 fere omnino, intermediis posterioribusque basin versus, pallidioribus ; abdo- 

 mine vel toto vel parte majori pallide flavo ; alis subhyalinis, nervis piceis. 

 Femina. 

 Long. corp. 5 * unc. Exp. alar. 5 7 3 unc. 



Variat genis luteis, clypei puncto concolori, vel disco omnino nigro. 

 Habitat in Epiro rubis exsiccatis cum praecedentibus. (An species distincta ?) 

 The dissimilarity in appearance between this and the preceding species is so 

 striking, that, although he inclined to consider the difference as resulting from 

 parasitical attack, it would perhaps be hazardous to assert this without further proof 

 of their identity. It is, however, remarkable that all the male parasites which he has 

 obtained were derived from these pale-coloured specimens, whereas the apterous fe- 

 males were restricted to the former, — a circumstance not unworthy of attention, as 

 connected with the physiology of sexual development. 



Sp. 3. HYL2EUS gibbus. 



Niger, gibbosus ; genis, tibiisque anterioribus antice, luteis ; posterioribus ad 

 basin, intermediis vix, tarsorumque quatuor posteriorum articulo primo, albi- 

 cantibus ; antennis subtus ferrugineis ; prothoracis lineola interrupta tenui, 

 humeris, alarumque squama, flavescentibus ; abdomine nigro ; alis fuscentibus, 

 nervis piceis. Femina. 



Long. corp. 3 lin. Expans. alar. A\ lin. 



Habitat in Epiro, quercibus prope Sinum Ambracicum. 



The Hylecthrus quercus was obtained from this species, the abdomen exhibiting 

 irregular rufous patches in some specimens parasitically affected. 



Having reared two new species from the bodies of bees of the genus Hylaeus, 

 Mr. Saunders availed himself of the opportunity to offer some remarks on these para- 

 sites, and certain particulars which had come under his notice. The first species he 

 obtained from oak-galls, which he had placed in a box and forgotten till some months 

 afterwards, when he found — on some Hylaei which had been produced and died — 

 abdominal protuberances caused by the presence of Strepsiptera, still in their pupa 

 envelopes, having perished in situ after attaining the imago state. The following 

 year he could find no more Hylaei in oak-galls ; but knowing that the larvae of these 

 bees nidificated in briars, he collected some briar-snags, and on the 28th of May se- 

 lected from their occupants five already-formed pupae, the remainder being still in 

 the larva state : of these, three completed their transformations within two days, when 

 he saw the usual parasitic phenomena, not previously apparent ; and the next morn- 

 ing, on placing them in the sun, two winged parasites— smaller than those previously 

 obtained from the Hylaeus of the gall — speedily came forth. The remaining selected 

 pupa; never attained the imago state. From the ample stock of larvae and briars re- 



