Holmes—Description of a Species of Eubranchipus. J'253 
of last abdominal segment orange; tip of stylets whitish. Swim¬ 
ming feet and claspers tinged with orange. A pair of blue 
spots above median eye and a bine area on onter side of egg sac. 
This species which is one of beautiful coloration was taken 
along with E. bundyi in small ponds near Madison, Wis., in 
April, 1907 and 1909. The two species were sometimes found 
in the same pond or pool and sometimes in separate ones, both 
make their appearance at about the same time and live for only a 
few weeks. 
Eubranchipus ornatus differs from E. bundyi in its much 
broader and more irregularly shaped frontal appendages, and 
in its claspers which are long and attenuated and end in a single 
point instead of a truncated and dentate tip. From E. serratus 
Forbes which it resembles in its frontal appendages it differs 
markedly in the form of the claspers which in the latter resemble 
those of bundyi , and in the segments of the abdomen which pre¬ 
sent no appearance of serration. E. vernalis Verrill of the 
eastern states, the only other species of the genus in Rorth 
America, has very different frontal appendages and claspers. 
Eubranchipus in ordinary daylight or even sunlight shows 
little phototactic response. Individuals placed in a glass dish 
do not congregate to any noticeable extent either on the side 
toward the light or away from it, but if taken into a dark room 
and exposed to a sharply localized source of light they at once 
manifest a quite decided phototaxis. They congregate on the 
side of the dish toward the light and will follow the light about 
in all directions. This behavior is similar to that of many 
insects which show no tendency to fly towards the sun while in 
the field, yet manifest a marked proclivity to go toward a win¬ 
dow or a lamp when brought into a room. The reason for this 
may be, as Radi has suggested, that when out of doors light falls 
upon the eyes from all parts of the sky and impulses to go in any 
one direction do not greatly preponderate over others; while if 
the light comes from one direction it is much more likely to 
produce orientation. 
When the light is moved from side to side Eubranchipus 
orients itself by a sudden movement of the tail toward the light. 
When one such movement does not suffice others are performed 
