318 



THAXTER. — MONOGRAPH OF THE LABOULBENI ACE7E. 



cell is never appendiculate in this genus, it is normally so in Rhadinomyres. There are also certain 

 differences in the antheridial branchlets which may be significant. Several allied forms are represented 

 in my South American material which has not yet been studied and it may be hoped that an examination 

 of these new forms may make a more definite conclusion possible. 



Of the species of Rhadinomyccs first described, I have found R. pallid/us in its typical form in the 

 British Museum, No. 441 on Lathrobium angustatum from Folkestone, England, No. 444; on L. quadra- 

 tum from Notting Hill, England; and also in the Hope Collection No. 226 on Lathrobium sp. from Eng- 

 land. A third species, possibly a variety of R. eristatus, has been found on several Lathrobia in America, 

 and was illustrated in my Monograph, Plate IX, fig. 10, as "Var. a." The same form, or one closely 

 allied, was obtained in the British Museum, No. 445, on L. termination Gr., from Eltham, and in the 

 Sharp Collection, No. 1144, on L. brunncipcunis from Thornhill, England. It is necessary, however, to 

 examine more abundant and better material of this variety before its limits can be determined. 



COR ETHROMYCES Thaxter. 

 Two typical species are added to this genus which correspond in all respects to the original type, and 

 also two peculiar forms on Stilicus which depart distinctly from this type. The relations of their antheri- 

 dia, however, appear to correspond to the type as may be seen in fig. 9, plate L, and their reference 

 here appears to be correct. 



Corethromyces Cryptobii Thaxter. Plate LI, fig. 3. 

 This species appears to vary considerably in size, the accompanying figure representing its extreme 

 development. The individual illustrated was associated on the same host with much smaller ones in 

 which the appendages form a shorter denser tuft; but in all cases there seem to be three main erect branches 

 of the appendage which, in connection with other details of structure, serve to distinguish it from the allied 

 C. Braziliensis. The figure is drawn from material found on specimens of Cryptobium kindly sent me 

 from Kansas by Professor M. A. Barber. 



Corethromyces Brazilianus Thaxter. Plate LI, figs. 1-2. 

 Proc. Am. Acad. Arts and Sci., Vol. XXXV, p. 432. June, 1901. 



Perithecium and receptacle much as in C. Cryptobii, but differing distinctly in the character of its 

 appendage, the inner main branch of which consists of from four to six cells, the others very short, all 

 nearly opaque, the branchlets long rigid divergent, curved abruptly outward at the tips. Total length to 

 tip of perithecium 200-375 fi. Spores 28 X3/i. Perithecia 90 175 X 28-38 p. Appendages to tip of 

 branchlets 140-200 fi. Two specimens from Colombia, apparently identical, are much larger; total 

 length G10 fi; branches of appendages 540 p.; perithecia 450 /<. 



On Cryptobium Brazilianum Luc, Paris Museum, No. 173, (Type) Brazil; on C. fasciatum Erichs, 

 Paris Museum, No. 197, Caracas, Venezuela; on C. Flohri Sharp, British Museum (Biologia Coll.), No. 

 702, City of Mexico; also from same collection on C. verm-stum Sharp, No. 758, Oaxaca, Mexico; on 

 C. similipenne Say, No. 7G1, Mexico. The larger type on Cryptobium sp. indet., British Museum, No. 

 385, Colombia. On all parts of host. 



This species seems clearly distinguished from C. Cryptobii in that its appendage produces only an 

 inner main branch, the rigid branchlets from which, together with the tuft of short external branches 

 from the main appendage, are bent outward in a characteristic fashion quite unlike that in C. Cryptobii. 

 The very large specimens (British Museum No. 385) from Columbia do not appear to differ essentially 

 from the typical form, and similar variations in size are common in C. Cryptobii. 



Corethromyces purpurascens Thaxter. Plate L, figs. 4-5. 

 Proc. Am. Acad. Arts and Sci., Vol. XXXV, p. 433. April, 1900. 



Perithecia dull purple, mostly slender straight or slightly curved, nearly isodiametric or the outer 

 margin convex; the base slightly broader, the junction of the basal and subbasal, and of the subbasal and 



