THAXTER. MONOGRAPH OF TIIK LABOULHKM ACK.K. 



Ill 



Laboulbenia gubbifeha Thaxter. Rate LXVI, Bg. L. 



Proc. Am. Acad. Arts and Sci., Vol. XXXV, p. 179. Dec, 18!)9. 

 Perithecium free or nearly so, somewhat narrower than in L. Dercyli, the apex narrower and more 

 abruptly distinguished, the lips distinct, turned slightly inward; an external outgrowth just below the 

 blackened tip, which it may exceed in length, forming a free protuberance straight or bent sidcwi.se or 

 inward, its apex evenly rounded or slightly inflated, its outer margin continuous witli the nearly straight 

 margin of the perithecium. Cells I and II of the receptacle faintly punctate, relatively long and stout, 

 nearly isodiametrie; cell II about twice as long, distally nearly as broad as the portion of the receptacle 

 above it comprising cells III and VI, which are about equal in length; the latter extending obliquely 

 somewhat lower btit little higher than the former, and much narrower; the region of cells II V more 

 deeply suffused and distinctly punctate with blackish brown points, the undifferentiated insertion-cell 

 pushed out by the enlargement of cells IV and V. Appendages consisting of a number of prominently 

 projecting basal cells, originating in part from the proliferation of cell V, which bear branches terminally 

 and unilaterally, distinguished by blackened septa; the branches once to twice branched, their basal 

 portion slightly suffused and with blackened oblique septa; the distal portion quite hyaline. Perithecium 

 150-167 X 50 [i. Total length to tip of perithecium 400-450 y; to insertion-cell 275-340 (i. Appendages 

 150 y. 



On Dercylus tenebriosus Laf. (Eurysoma tencbrioidest), Hope Coll. No. 328, Para; Brit. Mus. No. 

 580, "S. America." Inferior surface of thorax and prothorax near base of two anterior pairs of legs. 



Although this form is distinguished from L. Dercyli, with which it was associated on the same host, 

 by the peculiar outgrowth from its perithecium, by the arrangement of the distal cells of its receptacle, 

 and by the multiplication of its appendages through the proliferation of cell V, it may prove only a variety. 

 The curious perithecial outgrowth, however, is certainly not a structure which develops at late maturity; 

 since it appears well developed in the youngest perithecia; and in the sufficiently abundant material 

 available of both species, there are no transitional conditions. It should nevertheless be pointed out 

 that a similar outgrowth occurs in some specimens of the very variable L. Pulyhirma; (Plate LXV, 

 figs. 1-3) but in this case a variety of intermediate conditions occurs. As in the case of L. Dercyli, the 

 specific designation is provisionally retained and both may eventually have to be reduced to synonyms 

 of L. variabilis. 



Laboulbenia variabilis Thaxter. 



This species appears to be absolutely confined to the western hemisphere, although it extends through- 

 out the two continents. It is a very common and extremely variable form and occurs on a great variety 

 of hosts. Through the courtesy of Dr. Horn of Berlin I have been able to examine specimens on two 

 species on Tetracha from Ecuador, which differ in no essential respect from the typical forms, and are 

 the first members of the family which have thus far been seen on any member of the Cicindeliche. The 

 variations of the species in general are associated with rather extreme variations in size and coloration 

 and in the variable proliferation of the cells of the receptacle adjoining the insertion-cell which give rise 

 to a variable number of appendiculate cells. The following is a partial list of the additional material of 

 this species which has been examined since the publication of my Monograph. 



British Museum, No. 628, on Platysma caudicollis Dej., Buenos Aires; No. 658 on Poecilus- Mexi- 

 canus Chd., Mexico; No. 584 on Aspidoglossa sp., Louisiana: Hope Collection No. 333 on Pterostichus 

 sp., "New York"; No. 337 on an undetermined carabid from Valparaiso, Chile; Berlin Museum No. 

 868 on Omophron Americanum Dej., N. America; No. 914 on Brachygnathus fnlgidipcnnis Guer., Brazil; 

 No. 927 on Chlwnius Gundlachi Chaud., Cuba. U. S. National Museum No. 21, on CJilcenius chloro- 

 chrous Chaud., Central America; on Tetracha Horni Ruse, and T. fulgida Klg., Ecuador; received 

 from Dr. W. Horn of Berlin. 



