1900.] 147 



NOTES ON PEZOMACnUS. ♦ 



BT EENEST A. ELLIOTT, F.E.S. 



Pezomachtis is certainly a most difficult subject. Prof. Foerster's 

 Monograph is still the standard work ; but, although a great improve- 

 ment upon Gravenhorst, it now in the light of modern discoveries 

 requires some considerable revision to bring it up to date. 



Foerster dissected the Gravenhorstian genus Pezomachus, and 

 divided it into nine genera. Two of these may at once be eliminated, 

 namely, Pferocormus, the only species of which, Pt. means, has proved 

 to be a semi-apterous, or rather brachypterous, form of the female 

 Ichneumon latrator, and Agrothereutes, since Agr. Sopei is now shown 

 to be the female of Cryptus fygoleucus ; and the other species, if 

 indeed they are not mere colour varieties, will certainly find their 

 mates in the same genus. 



Starting with the idea that no member of the Pezomachus group 

 could possibly possess fully developed wings, Foerster at once 

 separates from it three species, namely : longipennis,fulveolatus,BMdt. 

 Mangeri, to which he gives the generic name of Catalytus. The first 

 named has the most fully developed wings and a partly black meso- 

 thorax ; while the others only differ from it in having less developed 

 wings, and the mesothorax entirely red ; hence it may very probably 

 prove that they are all one species. Again, the wings differ greatly 

 in different individuals, and there is absolutely no generic character 

 to separate them from Apfesis. Mr. Bridgman described a Catalytus 

 as a new species of Aptesis, under the name of AjJt. Foersteri ; and 

 a specimen of the same has been recently sent to me labelled 

 Aptesis ? hemiptera. 



Aptesis and Theroscopus are only separated by the length of the 

 wings, and the more or less complete development of the metathoracic 

 arese, which latter character seems also unreliable, as Mr. Bridgman's 

 Ther. niger has the thorax of an Aptesis, thus showing that there is 

 no clear distinction between these genera. All these three, Catalytus, 

 Aptesis, and Theroscopus, might be united under one name, and would 

 also include Mr. Marshall's Oresbius, which is distinguished only by 

 its unicolorous antennae. 



After the wings, Prof. Foerster takes the length of the aculeus, 

 Cremnodes having this organ less than half the length of the first 

 abdominal segment, while in the other genera it is usually more than 

 that length. This character does not appear to be constant, and 

 certainly in the case of Pez. Neesii it varies from being barely visible 



