THAXTER. MONOGRAPH OF THE LABOULBl \IACK-1 . 4-13 
to exist between the Exogense and the Kndogense, from the fact that a dbchaige tuhr is tlrvclojMM. and 
that the sperm cells appear to be quite free at the moment of exit, not remaining attached or coloring 
as they occasionally do in Rhynehophoromycrs. Although in Ceratomyccs and Autoicomycrx the sjhtii 
cells appear to be segments of actual branchlets, and in Zodiomyces they arise, if niv former observa- 
tions are correct, by exogenous budding as in the spermatia of many lichens, it is evident from these* 
intermediate conditions, that no hard and fast line can be drawn between the two types of origin. 
The species occur on water bugs, Corisidse, (often written Corixidae) , and are the only forms known 
to be parasitic on hemipterous insects. The discovery of this very interesting genua is doe to Mr. 
Charles Bullard who first observed it on Corisce from the Cambridge region. 
Coreomyces Coris^e Thaxter. Plate LXXI, figs. 16-18. 
Proc. Am. Acad. Arts and Sci., Vol. XXXVIII, p. 56. June, 1002. 
Curved or straight, pale dull brownish, nearly transparent. Cells of the receptacle distinguished 
by more or less distinct constrictions, the three lower somewhat variable in length, the basal smaller, 
usually tapering somewhat to the foot; the subbasal larger than either of the others, more or less inflated, 
often as broad as the perithecium; the upper cell somewhat narrower, followed by ihe two to tour, usually 
flattened, appendiculate cells, which are successively longer, though usually slightly narrow from beloi 
upward, the uppermost becoming about half as long as broad. The appendages long slender hyaline, 
sparingly branched, slightly divergent; usually extending upward to, <>r considerably beyond, the tip of 
the perithecium. Stalk-cell of the perithecium not differentiated from the cells below it, huge, as broad 
as the body of the perithecium above it, cylindrical or slightly inflated, about as long as broad or slightly 
longer: body of the perithecium usually straight, somewhat darker dull brown,, penally where it tapers 
rather gradually to the small tip which becomes distinctly symmetrically four-papillate, and i.s nsnalh 
slightly bent to one side. Spores 85 X 6 ft. Perithecia 100-110 X 25-35 ft, the stalk-cell 30 33 X 
32-35 ft. Receptacle, exclusive of the appendiculate cells, 75-100 ft. Appendages 200 2.50 ft. Total 
length to tip of perithecium 275-290 ft. 
On inferior surface of abdomen of Corisa Kcnnicottii Uhler, Arlington (Bullard), on Corua sp., Iowa. 
and on two species of the same genus collected near Fresh Pond, Cambridge. 
This species, which sometimes occurs in company with C. curvatm on the same individual, is always 
found on the abdomen, usually near its extremity, on the under side. In a single instance a group of 
individuals was found on the upper margin of one of the anal plates which differ in several respects from 
the type form, having as many as seven appendiculate cells, a more elongate form and other Blight differ- 
ences which may prove of specific value. The material from Iowa corresponds in all respects With the 
ordinary type found about Cambridge. The name of the host-genus is sometimes written Corixa. 
Coreomyces curvatus Thaxter. Plate LXXI, figs. 7-15. 
Proc. Am. Acad. Arts and Sci., Vol. XLI, p. 318. July, 1905. 
Nearly hyaline, or but faintly tinged with brownish. Receptacle becoming narrow toward the small 
basal cell, the two cells above the latter subequal in length, the appendiculate cells usually four, broader 
than long, subequal or the lower shorter. Stalk-cell of the perithecium relatively long, slightly or not at 
all inflated; 
upper third or more bent 
outward, tapering to the blunt curved apex, tne concave »mc ui »...*.« - ~~ & 
convex marked by slight indentations due to the prominence of the persistent wall-cells m this wrioii. 
Appendages as in L. Corists, usually distinctly shorter. Spores 55 X 4 ft. Penthecmm 130 140 X »* 
its stalk-cell 70 X 25 ft. Total length, average, about 350-360 ft. Appendage about 125 ft. 
On under side of margin of left elytron of two species of Corisa. Near Fresh Pond, Umbriijge. 
Sufficient material of this form has been obtained on Coris* from an old clay pit near Fresh Pond, 
to determine the constanev of its characters. Its occurrence on the left elytron appears to be mvanable. 
