204 PROCEEDINGS OF THE AMERICAN ACADEMY. 



1457, Isla de Santiago, La Plata; No. 1426 in Museo Nacional, no 

 locality; No. 2030, La Plata (P. Spegazzini). 



The present species adds still another form to the well marked 

 series of the L. Te.vana group, all of which occur on the inferior surface 

 or legs of species of Brachinus, and which I have hitherto preferred to 

 treat as varieties of L. Tcxana. Sufficient material of several of 

 these forms which is now available, indicates clearly that the members 

 of this series are better regarded as species, which correspond among 

 themselves in a fashion very similar to that which may be seen in the 

 much more numerous species which have developed on the allied 

 host-genus Galerita in the Western Hemisphere. Among these forms 

 Laboulbenia Oaxacana, alone, has not been found in the Argentine 

 region, although Laboulbenia pendula is known only from IVIonte- 

 video, and but a single specimen of what appears to be the t^'pical 

 L. Texana was obtained at the Isla de Santiago. 



Of the other members of the group the following were obtained. 



Laboulbenia incurvata exactly resembling the types, was found 

 on a large Brachinus in the Museo Nacional, No. 1427, labeled 

 "Argentine"; on several specimens of a Brachinus taken on the Isla 

 de Santiago, La Plata, and on a Brachinus collected in Tucuman by P. 

 Spegazzini. 



Laboulbenia retusa, which was first found in Florida, was again 

 obtained on Brachinus from the Isla de Santiago near La Plata, No. 

 1457, as well as from Tucuman No. 1939. 



Laboulbenia tibialis, also first obtained in Florida, occurred in 

 good condition on a Brachinus collected by P. Spegazzini in Tucuman, 

 No. 1939. All the seven species of this group occupy more or less 

 definite positions on the host, and none of them ever occur, as far as 

 has been observed, on the upper surface; although L. Brachini, 

 which is often associated with them, may be found in any position. 



Laboulbenia inflecta nov. sp. 



Basal cell of the receptacle hyaline or faintly suffused above, much 

 longer than broad, the receptacle above it uniformly dull yellowish 

 olivaceous and compact, the cells not greatly different in size; cell III 

 extending upward sometimes almost to the insertion-cell. Insertion- 

 cell somewhat oblique, thick, deeply suffused; outer and inner basal 

 cells of the appendage subequal, the outer externally rounded and 

 suffused, the axis of the outer appendage consisting of about five 

 obliquely placed cells; those above the basal cell small, their branches 



