176 SUMMARY OF CURRENT RESEARCHES RELATING TO 



in the gill-chamber. There was no evidence of parasitism ; it is likely 

 that the Vorticellae fed on the muscle juice diffusing in the water from 

 the flesh given as food to the tadpoles. 



New Genus of Dinophysidse.* — C. A. Kofoid describes from the 

 .San Diego region a new genus of Dinophysidse which he names Tripo- 

 solenia. He gives the following diagnosis : Dinophysidse with subequal 

 valves, transverse girdle encircling a small head, neck elongated, oblique 

 to anterior process which arises obliquely from a laterally compressed 

 mid-body. Two antapical horns, spreading, curved, approximately 

 balanced, the dorsal a trifle shorter tlian the ventral. The antapical 

 tips simple, with or without spinules, or projecting tubercles, or major 

 flexures, often with a distal sinistral deflection, thecal wall structureless 

 or pitted. Lists hyaline, ribbed, not excessively developed. Chromato- 

 phores yellowish green, if present. In oceanic plankton of warm, 

 temperate, and tropical seas, in the deeper levels, rarely at the surface. 



The author discusses tlie significance of the asymmetry of Tripo- 

 ^oUnia and other Dinoflagellates. It is adaptive to flotation. The 

 various types of asynnnetrv' all have the tendency to orient the passively 

 sinking organism broadside to the direction of descent, and thus to 

 increase the area of resistance. 



Structure of Vorticella monilata.t — 0- Schroder gives an account 

 of the external sheath and the myonemes of this Ciliate. The external 

 sheath consists of annular bands separated by grooves. The annular 

 bands are composed of cell-like structures with convex projections or 

 knobs. These cell-like structures often contain an internal corpuscle. 

 Besides the myonemes of the adoral spirals and of the vestibule, there 

 are longitudinal myonemes and annular myonemes in the peristomial 

 margin. Many other details are described. 



Blastodinidse.l — -E. Chatton describes Blastodinium priivoti g.etsp.n. 

 observed in pelagic Copepods (Calanidae) at Banyuls. The parasites 

 occur (from one to thirty in number) in the mid-gut, and by dilating 

 the stomach they compress the gonads, and thus mechanically castrate 

 their hosts. There is periodic segmentation of a mother-cell, giving rise 

 to successive generations of spores. The parasites are referable to the 

 Dinoflagellata, or Peredinians, but their peculiarities of habit and repro- 

 duction make it necessary to establish a distinct family. 



Parasites of Southern Sudan. § — Sheffield Neave gives an account 

 of parasites noted by him in a journey from Gondokoro to Meshra-el- 

 rek. Trypanosomes were found in the mule, four species of fish 

 {Bageus hayard, Synodontis schaL Miigil, and Polypterus), the red- 

 breasted shrike, vulture, and in one case in man. Filarm were found 

 in five species of birds, Halteridium in eight, and a new Hmnammha 



* Univ. California Publications (Zoology), iii. (1906) Nos. 6-8, pp. 93-133 

 (3 pis. and 2 figs.). 



t Arch. Protistenkunde, vii. (1906) pp. 395-410. See also Zool. Zentralbl., xiii. 

 (1906) pp. 593-4. 



X Comptes Rendus, cxliii. (1906) pp. 981-3 (5 figs.). 



§ Second Report, Wellcome Research Laboratories, Gordon Memorial College, 

 Khartoum, 1906, pp. 183-204 (6 pis.). 



