354 



MONOGRAPH OF THE LABOULBENIACEiE. 



On Gyrinus fraternus Coup, and several undetermined species, New England; on G. affinis 

 Aube, and G. ventralis Kirby, Middle States ; on G. analis Say, Missouri ; on G. confinis 

 Lee., Oregon ; on G. consohrinus Lec., and G. plicifer Lec., California ; on G. urinator Illig., 

 France. 



This remarkable species is by no means uncommon, and is so peculiar that it could by no 

 chance be confused with any other species. A comparison of its younger stages shows that it 

 corresponds in all essentials to the type structure of the genus, there being primarily a single 

 insertion-cell above cells IV and V, which are normally placed (figs. 32-34), while the append- 

 ages are developed originally from an inner and outer basal cell (fig. 34), as in species of the 

 usual type. The outer appendage consists at first merely of two or three roundish superposed 

 cells, terminally more or less bilobed, from which a certain number of branchlets may arise; 

 while the primary basal cell of the inner appendage by constant and successive division and 

 proliferation forms the broad base of insertion characteristic of the mature plant. How far cells 

 IV and V and the insertion-cell take part in forming this base through secondary divisions, the 

 opacity of the plant in this region renders uncertain. Cells I and II are sometimes quite elongate 

 and very slender; but as a rule the general habit is sucli as is represented in fig. 31. The out- 

 growths from the lip-cells are similar in a way to those occurring in Stigmatomyces virescens. 

 They are often irregular in form and frequently are but partially developed. L. cornuta is the 

 only other species of the genus having a somewhat similar outgrowth from one only of its lip- 

 cells. 



The trichogyne is highly developed (fig. 36) and peculiarly branched ; its terminal branch- 

 lets tending to grow sideways in between the bases of the appendages. I have thus far been 

 unable to determine the character of the antheridia in this species, and have even been led to 

 suspect that the antherozoids might be exogenous. It is quite uncertain, however, what their 

 nature really is. 



The species occurs along the outer margins of both elytra of its host, sometimes extending 

 to the free tip of the abdomen, often growing in dense tufts. The latter, like all the other 

 aquatic forms infested by members of the present genus, is one which swims on the surface of 

 the water, and is very common in ponds and ditches, or along the margins of streams. 



TERATOMYCES Thaxter. Plate X, figs. 1-17 ; Plate II, fig. 1. 



Proc. Am. Acad. Arts and Sci. Vol. XXVIII, p. 182; Vol. XXIX, p. 98. 



Receptacle consisting of three superposed cells surmounted by a more or less cup-shaped 

 terminal portion divided by vertical and oblique septa into a series of numerous small cells 

 arranged peripherally, from which arise numerous appendages which completely surround the 

 point of origin of the perithecia. Perithecia one to several (five), symmetrical, with single 

 stalk-cells. Appendages consisting of a short series of sympodial branches, bearing sympodial 

 branchlets directed outward, many terminating in sharply-pointed, beak-like, sterile, terminal cells. 

 Antheridia flask-shaped or beak-like cells, free from one another, superposed in a single verti- 

 cal external row arising from the lower segments of the appendages. Trichogynes copiously 

 branched and septate. Spores once-septate. 



