6 University of California Publications. [Zoology 



2. The so-called tactile bristles on the antennae do not show 

 such characters. But in the furcal bristles of a species of Cyclops 

 structures have been found which are probably nervous in char- 

 acter. 



3. The rostral prongs of Diaptonuis are innervated in a 

 manner similar to that of the aesthetasks. This would indicate 

 the sensory function of the rostrum. 



4. In several cases it has been seen that there are bipolar 

 cells situated far back in the abdomen, the central processes of 

 which unite before entering the thorax and pass as a single fibre 

 far forward toward the brain. 



Berkeley, California, 



December 14, 1905. 



