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Bulletin Wisconsin Natural History Society. [Yol. 10, Nos. 3-4. 
inserted by the male. Perhaps the use of these antennae in female 
Eubranchipi may be to force eggs or sperm from the ovisacs. 
Their shape would suit them for such a purpose and is character¬ 
istic in each species. 
A male that has copulated with a female and injected a sperm 
packet is soon ready to repeat the process. Several were observed 
to mate a second time within a few minutes. One male injected 
sperm into four different females during one hour and thirty min¬ 
utes on April 24,— i. e., at 8:45, 8:52, 9:48, and 10:10 a. m. 
The females showed two conditions in regard to the position 
of the eggs in the ovisac. In some individuals the eggs were yel¬ 
lowish in color and were carried high along the sides (in the 
Fig. 3. Evib ranchipus dadayi, showing egg-sac. a, unfertilized 
female; l), shows recently injected spermotophore projecting from egg- 
sac ; c, egg-sac of a female that is ready to deposit eggs. 
oviducts), thus leaving a clear space down the median ventral re¬ 
gion ; in others the eggs were larger, had a slaty color, and occu¬ 
pied the median ventral portion of the ovisac. Judging by obser¬ 
vations on other species (Baird, ’50; Packard, ’78) the former 
were unfertilized and the latter fertilized females. Baird (’50) 
in describing his observations on the genus Chirocephalus says:— 
‘‘The female begins to lay before she has attained her full size, 
and lays several times during the season. Each time the ova are 
transmitted from the internal to the external ovary the animal 
thiows off its skin.” Packard (’78, p. 422) in speaking of 
Enbranchipus vernalis says: “After copulating the eggs are 
emptied from the oviducts into the outer ‘uterine’ bag—where they 
undergo the process of segmentation.” Packard also maintained 
that, “in both the red and white races attempts were never made 
bv males on already copulated females with filled uterine bags.” 
But the writer observed several instances in which males attempted 
