248 



THAXTER. — MONOGRAPH OF THE LABOULBENIACE^. 



strictly intercalary in its origin, and its development may be compared to the trichothallic growth of 

 certain algse. 



Although from his observations on the relation of this parasite to its host, Cavara appears to be in- 

 clined to regard the Laboulbeniales generally as saprophytes, the occurrence of a number of rhizoidal 

 forms seems to render it quite certain that they feed on the juices of the insect which in this, as in a 

 majority of cases, are absorbed, without penetration, through the sucker-like foot. 



The genus is closely allied to the succeeding one, from which it differs especially in the possession 

 of an antheridium which is compound at maturity. 



Rickia Wasmanni Cavara. Plate XXXIV, figs. 1-13. 

 Cavara: Malpighia, Vol. XIII, p. 182, PI. VI, 1899. Thaxter: Proc. Am. Acad. Arts and Sci., Vol. XXXVIII, p. 

 39. Rick: Oester. Bot. Ztitschr., April, 1903, p. 163, with figure. Exsic, Rehm Ascomyceten, No. 1451. 



Basal cell about as long as, or longer than, the rest of the receptacle; the axial series of cells, ex- 

 tending to a point nearly opposite the middle of the perithecium; consisting of about six cells, more or 

 less; its lowest cell lying above the basal cells of the other two series: the anterior series consisting of 

 from four to five cells, the two lower longer, the lowest only occasionally appendiculate; the posterior 

 series consisting of usually five or six cells, exclusive of the two (rarely single) basal cells of the primary 

 appendage which terminates this series. The members of both the anterior and posterior series, with 

 the usual exception of the basal cell of the anterior series, cutting off a smaller cell distally and exter- 

 nally, which usually cuts off a second small cell; each of these bearing either sterile appendages or an- 

 theridia. Antheridia relatively small, flask-shaped, the venters evenly inflated and evenly curved to 

 the narrow necks which are about half as long as the venters. Secondary and primary appendages 

 hyaline, or suffused with brown, simple, mostly inflated, short. Perithecium somewhat asymmetrical, 

 its outer margin and distal half tapering to the somewhat irregular blunt, or truncate, hardly differen- 

 tiated tip. Perithecium 40-50 X 18-22 fi. Spores 28 X 2.5 fi. Total length to tip of perithecium, 

 average 150 p., maximum 200 Antheridia about 12 X 4 ft. 



On all parts of Myrmeca lecvinodes Nyl. Linz on the Rhine. (Wassmann.) 



This species is said to be abundant in the localities where it has been found, parasitizing a majority 

 of the individuals in certain nests of its host. I have thus far been unsuccessful in attempting to find 

 it in this country, where it seems to be replaced by the curious little Laboulbenia Formicarum. In ex- 

 ceptional cases, especially when the primary perithecium has been destroyed, or has failed to develop, 

 secondary perithecia may arise from one or more cells of the receptacle below, as is the case in Peyrit- 

 schiella and in other genera. 



DISTICHOMYCES Thaxter. 

 Proc. Am. Acad. Arts and Sci., Vol. XLI, p. 308. July, 1905. 



Receptacle consisting of a basal and subbasal cell, surmounted by two parallel series of cells of in- 

 definite number, any of which may bear either a sterile appendage, or an antheridium, externally; one 

 of the series ending in a perithecium, the other terminated by the primary appendage. Appendages 

 of the same type as those of Rickia and Peyritschiella. Antheridia at maturity terminal on a unicellular 

 branch, becoming quite free in a compact group. 



This genus is distinguished from Rickia by its ultimately free antheridial cells which are apparently 

 developed originally as in the typical compound antheridium. The terminal cell which would ordi- 

 narily form the common efferent tube being absorbed, or disorganized, so that the antheridial cells appear 

 to be quite free, as in the Laboulbeniinese, and of the same simple type, closely associated in a compact 

 terminal group. The very early development of the antheridium has not been seen in any of the speci- 

 mens examined, but the occurrence of a disorganization, like that described, seems clearly indicated by 

 the general appearance of the nearly mature antheridial branch, especially by the ridge which is present 



