396 S. J. HOLMES 



Actinobolus attacks the infusorian Halteria while Spathidium 

 captures Colpidium colpoda. If Spathidium is well fed it makes 

 no efforts to capture food. 



Moore (29) finds that negative phototropism in Daphnia 

 pulex is caused by ultra-violet light below a certain wave length, 

 and that the reaction may be reversed by the addition of small 

 amounts of C0 2 and HC1. 



Strychnine added to water containing positive and indifferent 

 specimens of Diaptomus caused a negative reaction in one 

 minute. Atropine produced the same change, but the effect 

 was not so decided, while caffeine produced a positive leaction. 

 Acids and camphor reveise the negative reaction caused by 



strychnine. 



In two papers Orton (31) (32) describes the natural history 

 and general feeding habits of Crepidula fornicata, with compari- 

 sons between the food habits of this species and those of other 

 mollusks. Several years ago Crepidula fornicata was introduced 

 upon the coast of England, where it is proving an enemy of the 

 oyster since it lives upon the same kind of food and thrives in 

 the same kinds of localities. The radula of Crepidula is not used 

 directly in feeding as it is in most gastropods, but is used as a 

 grasping organ for seizing the food. The food material, which 

 consists of minute organisms in the water, is brought in much 

 as in lamellibranchs by the action of cilia on the gills and 

 mantle chamber which sweep currents of food toward the mouth. 



Anemones will respond to a stimulus applied to the ectoderm 

 of the base of the column by a contraction ot the entodermic 

 muscles of the mesenteries. By a method of staining with 

 silver nitrate a nervous network may be demonstrated in the 

 lamella of the column, and through this network a connection 

 is established between the ectoderm and the mesenteric mus- 

 cles. Certain responses in animals whose ectoderm has been 

 anesthetized with magnesium sulphate are regarded by Parker 

 as a non-nervous direct response of the muscles. 



Pearse (34) has written an account of the general behavior 

 of fiddler crabs, treating of burrowing, feeding, pugnacity, fear 

 reactions and courtship. Like other crustaceans fiddlers show 

 no social instincts, although they commonly live in close asso- 

 ciation. The males aie pugnacious, attacking one another by 

 means of their large chelae. Occasionally males attack females, 



