47 
in which it is to be found at different times of the year. The records 
are confined to 1894 and 1895, when careful periodical surveys were 
made of the plant and animal life of the Illinois River and its connected 
lakes at the Biological Station. Although there were numerous dredging 
operations at different places in the river channel, the only specimen 
taken in this way was obtained December 18, 1894, at Station E, directly 
opposite a place on the shore where all our other specimens of H. forbesi 
were taken. In May, 1894, numerous specimens were found on both 
sides of the river at Station E, in the water-soaked banks, just above the 
water level. In the interval between April 13 and 23, 1895, numerous 
specimens were found at the same station, but in the west bank of the 
river only. Their abundance is indicated by a memorandum stating that 
29 specimens were taken from the mud obtained by an assistant by three 
successive scoops with the hands. At this time a careful search was 
made for specimens in other locations at various places down the river 
for nearly six miles, but none were found. 
Apparently they are nearer to the surface in April or May than at 
other times of the year. Just where they are during the remainder of 
the year is entirely unknown. Since H.emissarius is subterranean in 
habit, being collected chiefly from wells and tile drains, it seems reason- 
able to suppose that the new form also may have a subterranean habitat 
during most of the year. 
The time of sexual activity of H.forbesi is unknown. The speci- 
mens collected are all of about the same stage of development, with 
gonads quite large and often extending nearly to the posterior septum, 
but without any signs of cell-division activity. We have no records of 
partially grown, juvenile specimens. 
It seems probable that both H. emissarius and H. forbesi, and per- 
haps other species of the genus, actually occur in many parts of North 
America, but have thus far escaped notice except in Illinois. 
LITERATURE CITED 
Benham, W. B. 
04. On a new species of the genus Haplotaxis; with some remarks 
on the genital ducts in the Oligochaeta. Quart. Jour. Micr. Sci., 
48 : 299-322. 
Forbes, S. A. 
90. Note on an American species of Phreoryctes. Am. Nat., 24: 
477-478. 
90a. On an American earthworm of the family Phreoryctidae. Bull. 
Ill. State Lab. Nat. Hist., 3 : 107-116. 
Michaelsen, W. 
99. Beitrage zur Kenntniss der Oligochaten. Zool. Jahrb., Abth. f. 
Syst., Geogr., u. Biol. d. Thiere, 12 : 105-144. 
05. Die Oligochaeten des Baikal-Sees. Wiss. Ergebn. Zool. Exped. 
Baikal-See unter Leit. v. A. Korotneff, 1 Lief., pp. 1-68. 
