158 Phylum Plathelminthes 



nutrient fluid for 3 hours in the morning and for 3 hours in the afternoon, 

 and during the remainder of the day were maintained in the salt-dextrose 

 solutions. By this method the young worms were kept alive for 6 days in 

 the incubator and for 14 days at room temperature, but they did not 

 grow and apparently lived no longer in the veal broth than when the 

 products of protein decomposition were absent. 



Specimens of Crepidobothrium lonnbergi were removed from the in- 

 testine of Necturus and washed in sterile Ringer's solution. They were 

 then transferred to a sterile isotonic salt-dextrose solution. The medium 

 was modified by the addition of different amounts of Hottinger broth 

 prepared by the digestion of veal, and a series of cultures were prepared 

 with pH values from 6 to 8. The cultures which varied around pH 7.3 

 seemed most favorable. The worms were kept in small petri dishes at 

 room temperature and transferred to new media every 12 hours. In one 

 experiment, young specimens were kept alive for 32 days. During this 

 time they increased 3 to 4 times in length and the terminal portion of the 

 strobila became definitely segmented, but the proglottids were abnormal 

 and sterile. Addition to the media of salt extracts of the intestinal mu- 

 cosa, pancreas, and liver of Necturus, sterilized by filtration, did not 

 appreciably alter the rate of growth or time of survival. The exclusion 

 of free oxygen by anaerobic culture methods did not affect the result. 

 Fresh serum from Necturus was definitely toxic to the worms. 



Bibliography 



Stunkard, H. W. 1930. The life history of Cryptocotyle lingua, with notes on the 



physiology of the Metacercariae. J. Morph., 50:143. 

 1932. Attempts to grow cestodes in vitro. J. Paras. 19:163. 



Order monopisthodiscinea 



EPIBDELLA MELLENI 



Theodore Louis Jahn, State University of Iowa 



Occurrence. Epibdella melleni is ectoparasitic on the eyes and epi- 

 dermis and sometimes in the gill and nasal cavities of numerous marine 

 fishes of the order Acanthopteri. It is believed to be a West Indian 

 species, but it now occurs in the New York, Chicago, and Philadelphia 

 public aquariums. A list of susceptible and of non-susceptible fishes was 

 given by Jahn and Kuhn ( 1932 ) , and this has been checked and extended 

 by Nigrelli and Breder (1934). 



Life History. The anatomy of the adult and the complete life history 

 of the species were described by Jahn and Kuhn (1932). The eggs are 

 tetrahedral and are shed singly into the seawater. These may fall free 

 of the fish or may be caught on the gills, scales, etc., by means of filaments 



