1915] MacCallum: Ectoparasitic Trematodes 405 



and composed of ten or fifteen large round glands with very 

 long ducts. Cirrus quite long, a good deal curved and with an 

 oval bulbus ejaculatorius which appears quite muscular. Testis 

 lobulated. These differences from the other species described 

 force me to regard this as a new species for which the name of 

 Diplectanum longiphallus is proposed. 



Measurements of Diplectanum longiphallus. 



Length 95 mm. 



Width 15 mm. 



Length of cirrus .25 mm. 



Length of disc .08 mm. 



Width of head 05 mm. 



Egg .02 mm. 



Atalostrophion sardae, nov. gen. & nov. sp. 



(Figs. 137 and 138) 



During the summer of 1912, I first found on the gills of 

 the bonito, (Sarda sarda) by washing, a number of fragments 

 of a small, flat, ribbonlike worm. It was always found to be 

 broken at the end, but when stained and mounted it was seen 

 to contain internal organs of a tubular form; that is, there 

 were two, sometimes three tubes containing eggs, which were 

 portions of the uterus. Between these uterine tubes was a 

 brownish tube containing brownish yellow granules — the vitel- 

 larium — and besides these could also be seen the tubular testis 

 and a vas deferens containing spermatozoa. No matter how 

 many pieces were examined from the gills, they were always 

 imperfect ; both ends being torn across. This was the case dur- 

 ing 1912 and 1913, although very few bonitos came to autopsy 

 in the laboratory. However, it was determined in 1914, that 

 an attempt should be made to find out the origin of the pieces 

 and to secure a whole worm if possible. As a result of this 

 determination sixteen bonitos were examined in all and seven 

 of them found to be infested with the worm. It was then dis- 

 covered that the worm had its habitat not in the gills of the fish, 

 but was found in great numbers under the mucous membrane 

 of the branchial cavity on each side of the isthmus, and also was 



