434 



THAXTER. 



MONOGRAPH OF THE LABOULBENIACE^E. 



Sufficient material of this species was obtained from alcoholic specimens of its host, and is in very 

 good condition. The cells of the receptacle often appear to be longitudinally divided as in fig. 1; but the 

 smaller apparent cell is merely a space between the general envelope and the cell-wall proper. The spe- 

 cies is most nearly related to R. clcphantinus, from which it is distinguished by its smaller size, more 

 slender habit, shorter appendages, amber-brown color, and by the more numerous and differently formed 

 tooth-like outgrowths from the perithecial neck. 



AUTOICOMYCES nov. gen. 



Ceratomyces Thaxter pro parte. 



Receptacle consisting of three superposed cells, the lowest often involved by the blackened foot, the 

 upper surmounted by a pair of cells giving rise to the single perithecium and the antheridial appendage 

 respectively. Antheridial appendage consisting of a series of superposed cells producing ramigerous 

 branches irregularly along its inner margin. Perithecium usually appendiculate, determinate, the wall- 

 cells in rows of seven and eight members. 



This genus which I have already pointed out, is very nearly related to Ceratomyces emend., differs 

 in the constant and comparatively small number of cells forming the rows of wall-cells in the perithecium; 

 the inner and outer rows having eight and the lateral rows seven in all species examined. All the known 

 forms inhabit species of a single genus, Berosus, a fact which has suggested the generic name, and of the 

 six that have been described, one occurs in the East Indies, while the rest are American. In addition 

 to the three forms illustrated herewith, three others, Autoicomyees furcatus, A. distortus and A. humilis 

 were formerly included in Ceratomyces and it may be mentioned that a seventh species is known to occur 

 on Berosus in South America. All the species have a certain family resemblance and are for the most 

 part pale, or quite hyaline. A. humilis, of which good material has been again obtained from the type 

 locality, is the only form which lacks a perithecial appendage, the conformation of its tip being rather 

 exceptional, the edges spreading somewhat and pointed, not compressed as in the other species. A. 

 contortus has also been found on the same host in the vicinity of Fresh Pond, Cambridge, but the other 

 New England species have only been met with in the small pond, formerly referred to, on the highest 

 point of Cutt's Island, at Kittery Point, Maine. 



Autoicomyees acumjnatus nov. comb. Plate LXVIII, fig. 8. 



Ceratomyces acuminatus Thaxter. Proc. Am. Acad. Arts and Sci., Vol. XXXV, p. 447. April, 1900. 



Hyaline. Receptacle consisting of three superposed cells, the basal cell partly suffused and con- 

 tinuous with the blackened foot. Perithecium rather stout, the outer margin nearly straight, the inner 

 strongly convex; the seventh wall-cell of the inner row greatly enlarged, its outer wall very thick, forming 

 an erect tapering bluntly pointed terminal appendage, at the base of which the papillate apex of the lip- 

 cells projects on the right side; the fifth cell of the external row of wall-cells growing out to form a sub- 

 terminal slender appendage, eight-celled in the type, distally attenuated, its terminal cell bearing one or 

 two slender branches. Appendages consisting of from four to five superposed cells, the distal ones ap- 

 pendiculate (the branches mostly broken). Perithecium 185 X 40 [i. The appendage without branches 

 82 n, the branches 150 p.; the rostrate terminal cell 50 X 17 [x (at base). Receptacle 85 X 48 {i. Spores 

 about 70 X 3.5 p.. Appendage, broken, without branches 70 /i. 



On the inferior surface of abdomen and thorax of Berosus sp. indet. Eustis, Florida, October. 



A few specimens of this well marked form were found in Lake Eustis on a Berosus very like B. striatus. 

 The conformation of its tip and the character of its perithecial appendage distinguish it from other species 

 of this genus. 



