250 NOTES. 



diiferent from a typical JEJ. tmnsversus, but nevertLeless I believe it to 

 be the same species. 



£. vittatus JNIacq. The description agrees with E. tntnsvcrstis , ex- 

 cept that the eyes are said to be glabrous. But this statement is very 

 probably erroneous, as, with the exception of E. acncufi^ all the known 

 N. A. JErist((Us have pubescent eyes. 



E. pumilus Macq., seems to be based on a very small specimen of 

 E. trfmsver-'ins, in the variety with yellow anterior legs. I have not 

 seen the type in Paris. 



230. Eristal's Acdroclus, frater, chalepus Walker, which I have seen 

 in the Britisch Museum, are HdophiJi of the group of H. horecdh, 

 gwoilmnliaif!, glacialis. As it was not possible for me to determine 

 their synonymy, I have omitted them in the lists. 



231. Plagiocera boing preoccupied by King, (Hymenoptera 1S34), 

 Mr. Loew gave another name to this genus. It was, I suppose an over- 

 sight on his part, that he omitted to state that Ptcroptila was merely a 

 new name for an old genus. Schiner (Novara, 366) was right in su- 

 specting it 



232. HelopMlus. Compare the paper on the European species of 

 Hdopliilns by H. Loew, in the Stott. Ent. Zeitschr. , Vol. VII; several 

 North American species are described in it. 



233. Helo.hilus stipatus and H. /.naus'S Walker. I saw both in 

 the Brit. Museum. The former, I thought, was Hd. UDcatiis male. T)ie 

 latter, a greasy specimen, was undistiuguishable, but the descdptiou 

 shows it to be H. liiKatus. 



234. HelopMlvs obtcurus. The patria as given by Mr. Loew in the 

 Centuries (CarohiKi), was based upon an erroneous reading of the label. 



235. Eumerus porcus Walker, which is a Helophilus, is a very 

 peculiar species; it is represented in the Brit. Mus. by two {S and $) 

 welljireserved specimens. I have never seen it elsewhere. 



236. Helophilus s'^surrans Jaenn. The synonymy does not seem 

 doubtful; only II'Ddcrrand should be read instead of Seitcurand in the 

 description; without this emendation the comparison with H. poidulus 

 has no sense. 



237. Teuohocnemis. Milesia Bacuntius Walker, and Pterallastes 

 lituratus Loew, are closely allied and must be put in the same genus. 

 Both have, in the male, curved hind tibiae, with a strong projecting 

 spur in the middle, a character which is wanting in Plendlat^tes titoracicits 

 Loew. The latter was described by Dr. Loew in both sexes, and there- 

 fore must be considered as the type of the genus , while of P. lituratus 

 Dr. Loew described only the female. Hence arose the necessity of 

 establishing a new genus for the other two species. 



238. Teuchocremis Bacuntius. The specimens which I have from 

 Texas do not quite agree with Mr. Walker s description of the thorax, 

 nevertheless the identity is not doubtful. 



23J. Merodon Bautias Walker, is represented in the Brit. Mus. by 

 a single male specimen; 21. hipartitiis by four specimens, two of which 

 seem lo be femxles of M. Buutius; the two others may be a different 



