Plathelminthes. 105 



256) Boulenger, C. L. (Birmingham, University), On a Freshwater Medusa from 

 Rhodesia. In: Quart Journ. Micr. Science. 57, 4, S. 427 — 43«, 1 plate, 1912. 



Describes a new species of Liiiinocnida {L. rhodesiae) from Rhodesia. 



Doncaster (Cambridge). 



Plathelmintlies. 



257) Chi!«], C. M. and McKie, E. V. M., The Central Nervous System in 

 Teratophthalmic and Teratomorphic forins of VJanaria doroto- 

 cephala. In: Biol. Bull. XXII, No. 1, December 1911, S. 39 — 59, 31 figs. 



The senior author has classified as teratophthalmic those individuals of Fla- 

 tiaria in which the eye shows some departure from the usual structure or arrange- 

 ment, the head being normal in form. The teratomorphic heads present more 

 extreme abnormalities , involving not only the eyes but the shape of the head 

 and Position of the auricles. There is usually but a Single median eye, and the 

 auricles appear on the front of the head, either separate or more or less com- 

 pletely fused. 



„1. The teratophthalmic and teratomorphic forms of Planaria dorotoccphala 

 can be produced experimentally b}^ decreasing the rate of the dynamic processes 

 in the isolated pieces below a certain variable level which is necessary for the 

 production of normal forms. 2. In these forms the cephalic region of the ner- 

 vous System differs more or less vv^idely from that of normal animals. The two 

 ganglionic masses are always less completely separated than in the normal ani- 

 mals and often only a Single ganglion develops. In the teratomorphic forms the 

 ganglia are more abnormal than in the teratophthalmic forms. 3. In the normal 

 animals the cephalic ganglia extend a considerable distance anterior to the eyes 

 and the two separate nerve cords arise near the level of the auricles. In the 

 teratophthalmic forms with partially fused eyes the eyes lie nearer the anterior 

 end of the ganglia and the right and left portions are not separated at the level 

 of the auricles. The eyes of the teratomorphic forms are situated at the extreme 

 anterior end of the ganglionic mass. 4. The abnormal structure of the nervous 

 System in the teratophthalmic and teratomorphic forms continues posteriorly 

 through the regenerated anterior end to the level of the old tissue and even the 

 nerve cords in the old tissue may be more or less different from the normal. 

 In some teratomorphic forms the regenerated nervous tissue apparently begins 

 to break up into separate nerves a short distance posterior to the eyes, but re- 

 sumes the form of two nerve cords in the old tissue." Lillie (Chicago). 



258) Patterson, J. Thomas, Early Development of Graffilla gemelli- 

 para. A supposed Case of Polyembryony. In: Biol. Bull. XXII, No. 3^ 

 February 1912, S. 173—204, 6 plates. 



This is a viviparous Rhabdocoele commensal with Modiolus pUcatulus. It 

 was first described by Linton (Journ. Exp. Zool. Vol. 9, 1910), who noted the 

 occurrence of two embryos in each egg-capsule and suggested that it might be 

 a case of polyembryony. The author presents a careful study of the structure of 

 the reproductive organs, the nutrition of the ova and the formation of the egg- 

 capsule, of the Insemination, maturation and early cleavage, which show con- 

 clusively that the two embryos are not the product of a single fertilized eggy 

 but arise from two ova enclosed in a common envelope. Lillie (Chicago). 



259) Kreuter (Erlanger chir. Klinik), Über den praktischen Wert der Komple- 

 ment bindung für die klinische Diagnose des Echinokokkus. In: Beitr. z. 

 klin. Chir. 76, 3, S. 829—832, 1911. 



