1913] 
Pearse , Notes on Eubranchipus dadayi. 
113 
The males were for the most part ever ready to grasp females 
with their claspers if given an opportunity, and, when kept by 
themselves, were sometimes seen to clasp other males. If a male 
was placed in a dish with an unfertilized female he usually clasped 
her every few minutes until copulation took place, and sometimes 
even after that. Two often clasped the same female. After clasp¬ 
ing, a male usually attempted to insert his penis several times 
before he was successful. He grasped the female about the body 
from the dorsal side in front of the egg sac and bent his own body 
underneath hers, first on one side of her, then on the other, until 
he fmally introduced his penis or was shaken off. Males showed 
no preference (i. e., right or left handedness) in the side of the 
female they first attempted to use or finally used. The average 
time that actual copulation occupied after the insertion of the 
Fig. 2. Eubranchipus dndayi. Copulation. 
penis was t.88 minutes for twelve instances recorded. While a 
pair were in copula the male spread his frontal organs out along 
the female’s back, and rather jerky rhythmical contractions could 
be observed in his vasa deferentia. Packard (’78) says that in 
Eubranchipus vernalis copulation is always terminated by the male 
giving a few jerks with his “post-abdomen,” but in alPcases ob¬ 
served by the writer the female wriggled away from the clasp of 
the male. Copulation took place at the surface of the water or 
in the bottom of a dish. After it was over the female always be¬ 
came quiet and lay on her back at the bottom for some little time. 
A white mass of sperm could be seen at the posterior ventral angle 
of her ovisac and sometimes a white spermatophore projected a 
little way from its opening. One female after copulation bent her 
head over and with her second antennae forced out the white mass 
