540 A DESCRIPTION OF THE ENTOZOA COLLECTED BY DR WILLEY 



nothing of any flame-cells. The walls of the vessels are lined with a thin cuticle 

 on which rests an occasional nucleus. The most interesting feature apart from the 

 ciliated excretory vesicle, if the cilia really exist, is the presence of numerous recesses 

 or globular diverticula along the whole course of the vessels (Fig. 7, Plate LIV.). In 

 sections these diverticula give the idea that the vessel is splitting into branches but 

 as one passes on to the next two or three sections it becomes evident that no 

 branching is taking place but that an almost spherical bulging of the wall of the 

 tube has occurred. The rim which lies between these globular diverticula and the 

 lumen of the vessels is thickened at the edge and presents the appearance of a valve 

 such as has frequently been described in the excretory tubules of the Cestoda 

 <Fig. 7, Plate LIV.). 



II. DISTOMUM VENTRICOSUM Pallas var. minor. 



G. R. Wagexer. Arch, Naturg. 26th Jahrgang, I. 1860, p. 166. 



R. MoLiN. Denk. Ak. Wien, xix. 1861, p. 209 (D. ocreatum). 



P.-J. VAN Beneden. Mem. Ac. Belgique, xxxviii. 1871, Les Poissons des Cotes de 

 Belgique, p. 68. 



This parasite, for whose identification I am indebted to Professor M. Stossich of 

 Trieste, has hitherto been found in certain species of Clupeidae. Dr Willey took his 

 specimens from the stomach of a Sea-bream, Pinielepterus sp. in New Britain. 



11. CESTODA. 



I. BOTHRIOCEPHALUS PLICATUS Rud. 



C. M. DiESiNG. Systema Helminthum, Vindob, 18.50 — 1851, p. 591. 

 This work contains a list of synonyms and references to literature anterior to the 

 year 1850. 



G. R. Wagener. Acta Ac. German. Vol. xxiv., Supplement, 1854, p. 71, PI. VIII. 

 figs. 94 and 95. 



T. S. CoBBOLD. J. Linn. Soc. Vol. IX. 1868, p. 200. 



P. Olsson. Acta Univ. Lund. Vol. iv. 1867—8, Article VIIL, p. 11. 



Dr Willey brought home with him some portions of the intestine of the sword- 

 fish found in the Indian and Pacific Oceans, Histiophorus sp. which were crowded 

 with a Tape-worm. This I take to be the species Bothriocephalus plicatus of Rudolphi 

 recorded from Xiphias gladius L., the better known sword-fish. 



It is unfortunate that it was impossible to determine the species of the host 

 but as Giinther' remarks, "The distinction of the species is beset with great difficulties, 



' An Introduction to the Study of Fishes. Edinburgh, 1880. 



