a Genus of Dipterous Insects. 293 



rudimento. Thorax niger, postice dentibus a tergo duobus subulatis, flavis, 

 et utrinque solitariis ad latera. Alee binse, hyalinae, versus apicein anteiius 

 puncto nigro. Abdomen (Ichneumonis) clavatum, subpedicellatum, arti- 

 culis duobus ultimis nigris. Pedes flavi, femoribus anticis clavatis." 



The above is a transcript of the Linnaean characters ; but from a careful 

 inspection of the original figures, several additional peculiarities are noticeable 

 which do not exist in the description. In the latter, the two terminal abdo- 

 minal segments alone are stated to be black, but in the figure the last three 

 joints are represented as more darkly coloured than the anterior part of the 

 abdomen. In the description no notice is taken of the situation of the ocelli, 

 nor of the terminal spines of the femora, both of which characters appear in 

 the figure. The existence of. spines upon the ocular peduncles neither appears 

 in the description nor figures. As to the colour of the base of the abdomen no 

 statement is made ; but as the terminal segments are mentioned as being 

 black, it is evident that the preceding joints must have been of a diflferent 

 colour, which, from analogy, may fairly be considered to be red. As to the 

 situation of the spot of the wing, it is quite clear, not only from Linnseus's 

 description, " versus apicem anterius puncto nigro," but also from the figures, 

 that the spot is not terminal, but placed at a short distance from the extremity 

 of the wing. From the figures (which, however, in this respect are doubtless 

 inaccurate,) it would seem tliat the ocular peduncles are more erect and less 

 divergent than in the other species. Dalman has drawn up his description of 

 this species from a comparison between the original description and figures, 

 deeming the latter to be more deserving of attention than the former, to the 

 correctness of which, however, I cannot agree ; hence he is induced to con- 

 sider that Linnseus's insect was a female, probably because the abdomen is 

 clavate, and the ocular peduncles are only "longitudine thoracis ;" these cha- 

 racters, however, as we have already seen, are not conclusive as to the sex. 

 He also says, " Antennae pallidse seta nigra," although Linnaeus is silent as to 

 the colour of these parts. He adds, " coUarl rufescenti," whilst Linnaeus 

 says, " thorax niger :" it is true, that in Linnaeus's figure the collar is repre- 

 sented of as light a colour as the head, but I think that Linnaeus would not 

 have omitted to mention the difference in colour of the front of the thorax, if 



2 Q 2 



