ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 47 



•while Dr. Dobson is of opinion that it forms the type of a new order of 

 Vermes intermediate between the Trematoda and the Eotifera. The 

 following points would seem to indicate the Nematoid character of 

 this endoparasitic form : the general form of the body is terete, the 

 mouth is simple and subterminal, the regularly arranged leaflets are 

 simply extensions of the integument, supported by chitinpus fibres ; 

 there is no external or internal indication of any annulose segmenta- 

 tion of the body. The intestine is at first straight, then forms a 

 sigmoid curve, and then after another short straight piece coils spirally 

 round the spiral rachis of the ovary. There were 73 pairs of the 

 lamellar processes. 



Excretory Organs of Trematoda and Cestoda.* — M. J. Fraipont 

 has a third note on this subject, in which he gives an account of his 

 further investigations on the endoparasitic Trematodes of marine fishes 

 and on a species of Bothriocephalus. Of the former, he says that he 

 always found in it the ciliated infundibula. In the scolex of Tetra- 

 rhynchus tenuis, Professor Francotte has observed, and M. Fraipont 

 confirms the observation, that in the young cystic stages when the 

 scolex is hardly developed, there is, independently of the foramen 

 caudale and the two large longitudinal trunks, a system of fine 

 canaliculi terminating by ciliated funnels. In the complete scolex, 

 while still encysted, the two longitudinal canals bifurcate and penetrate 

 into it to form four longitudinal trunks ; these form a complicated 

 plexus in the head. In the Scolex trygonis pastinacece, which is 

 especially suitable for these studies in consequence of the great 

 transparency of the tissues, the two canals give off here and there 

 lateral branches which traverse the superficial layer of the paren- 

 chyma, pass through the delicate cuticle of the body, and open directly 

 to the exterior ; both the larger and the smaller canals are contractile, 

 and the author has been able to observe the expulsion of part of the 

 contents by the lateral secondary orifices ; the smaller branches are 

 more numerous towards the anterior than the posterior region of the 

 body. 



Having described the arrangement in BotJiriocepJialus pundatus, 

 the author concludes by observing that the fact that there is this 

 secondary communication with the exterior for the renal apparatus, 

 that there is a tendency to a symmetrical repartition of these orifices, 

 that in B. pundatus they are found in each segment, and that this 

 form has no terminal pulsatile vesicle, lead one to imagine how an 

 excretory apparatus, primitively single in the lower Platodes, may be 

 transformed into the arrangement seen in other and higher forms ; 

 into, that is, veritable segmental organs, independent of one another, 

 and similar in each segment. But, as he justly observes, the develop- 

 mental history has still to be worked out. 



Anatomy of the Liver-Fluke.t — Dr. F. Sommer has an essay on 

 this important and, at this time, peculiarly interesting form. The 

 broad and flattened body of Bistomum hepaticum has an oral orifice at 



* Bull. Acad. K. Sci. Belg., L. (1880) pp. 265-70. 



t Zeitschr. wiss. Zool., xxxiv. (1880) pp. 539-640 (6 pis.). 



