270 THE CANADIAN ENTOMOLOGIST, 



shows no trace of any longitudinal groove, such as is present in the type 

 of macrocephala. However, the length of the third segment of the 

 antenna as compared with that of the seventh or eighth in the two species 

 should be sufficient to show that the two are not identical in any case. 



Isodotitia apicalis. Smith, has sometimes been considered as a 

 synonym of Sphex philade/phica, Lep. . but I regard this as based on 

 insufficient evidence. Lepeletier's description gives no characters which 

 would place it in the more recent genus Isodofitia, and in two points 

 differs from what has been commonly considered that species. Lepeletier 

 says (Histoire Naturelle des Insectes. Hymenopteres, III., p. 340) : 

 "Thorax niger, nigro villosus," and " tarsorum quatuor anticorum articulo 

 extremeo ferrugineo." None of the many specimens of what has been 

 considered this insect which I have examined agree in these points with 

 this description. An attempt to locate the type in order to settle the 

 matter has proved a failure. The insect was in the Serville collection, and 

 this is not at the Museum d'Histoire Naturelle at Paris, and Monsieur R. 

 du Buysson writes me : " lis out du etre vendus et separes dans beaucoup 

 d'autres collections. Actuellement Ton ignore oii ils se trouvent." I may 

 add that Dr. F. Fr. Kohl, of Vienna, who has given much study to this 

 group, writes me : " Wahrscheinlich ist Sph. philadelphicus Lepeletiers 

 gar keine Isodontia." 



Under these conditions it seems best to apply Smith's name — 

 apicalis — to this insect, at least until Lepeletier's type shall be found. 



hodo7itia exornata, n sp. 



Head : clypeus somewhat arched laterally, with a feint median carina 

 most pronounced posteriorly, sometimes not perceptible ; anterior edge 

 slightly prolonged laterally, with a slight notch at the middle; surface 

 covered sparsely with yellow hairs. Clypeus and frons to level of inser- 

 tion of antenuce golden pubescent. Mandibles two-toothed, black at base 

 and tip 3 elsewhere ferruginous. Eyes somewhat nearer at the clypeus 

 than at the vertex. Antennse, first six to eight segments ferruginous, 

 terminal segments black ; scape bearing a few yellowish hairs ; third 

 segment longest. Head with scattered punctures and sparsely covered 

 with long yellowish hairs. A narrow, yellow pubescent band just behind 

 the eye. 



Thorax : collar faintly punctured, clothed with scattered yellow 

 hairs ; its dorsal edge and the posterior edge of the prothoracic lobe 

 golden pubescent. Mesonotum black with yellow hairs, rather coarsely 



