582 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Nervous System of Polystommn integerrimum.* — J. Andre gives 

 a detailed account of the cerebral ganglia and the nerves arising from it. 

 There is more resemblance to what obtains in a rhabdoceel Turbellarian 

 than to Tristomum or to Temnocephala. 



Eyes of Polystomum integerrimum.f — J. Andre describes the eyes 

 of the adult parasite, which are very remarkable in showing so little 

 trace of reduction. There is a sensory cell with a " rod-cap," and with 

 a nerve-process to the brain. What is even more remarkable is the 

 presence of a pigment-cup with an associated matrix-cell. 



New Species of Proteocephalus.J — G. R. Larne describes Proteo- 

 cephalus filaroides sp. n. from the small intestine of Amblystoma tigrinum. 

 The adult tapeworm and the plerocercoid larva? are both abundant. The 

 facts hint at direct development in one host. The new species is nearly 

 related to Proteocephalus lonnbergl in Nectarus maculatus. Both have 

 a peculiar end-organ, un unsegmented neck, a relatively thin and flat 

 strobila, and relatively weak musculature. Their excretory and repro- 

 ductive systems are much the same. 



Diplogonoporus brauni.§ — N. Leon reports a second occurrence of 

 this tapeworm (in a Roumanian woman), and gives a description of the 

 specimen. The reproductive organs were immature, as in the first 

 specimen, so that the systematic position of the species remains 

 uncertain. 



Parasitic Turbellarians.|| — Bruno Wahl describes a new genus, 

 Umagilla, in the family Dalyellidre (Vorticidse). The diagnosis reads : — 

 Dalyellids with a large doliiform pharynx near the anterior end, compact 

 paired testes, branched yolk-glands, unbranched paired ovary, and a 

 genital opening near the posterior end. The species U. forsJcahnsis was 

 found in Holothuria forskalii, which also harbours another Dalyellid, 

 Anoplodiwn (jracile Wahl. The author has also some notes on Syndesmis, 

 another genus in the same family. 



North American Turbellarians.1I — Ludwig von Graff gives a pre- 

 liminary account of a study of Xorth American Turbellarians. He has 

 added 30 to the list of 44 known American species, and 24 of the species 

 are new. Seventeen species are common to Europe and the United 

 States. 



Experiments on Cleavage of Cerebratulus Ovum.** — N. Yatsu has 

 obtained the following results : — The mode of cleavage is not disturbed 

 by the removal of a portion of cytoplasm, unless the operation is 

 performed close to the beginning of the first cleavage. If a portion of 

 cytoplasm, whether from one or two blastomeres, is removed during the 

 first cleavage, the mode of cleavage is disturbed. Slight injury or a 



* Zeitschr. wiss. Zool., xcv. (1910) pp. 191-202 (11 figs.). 

 t Tom. cit., pp. 203-20 (13 figs.). 



% Trans. Amer. Micr. Soc, xxix. (1909) pp. 17-49 (4 figs.). 

 § Centralbl. Bakt. Parasitenk., lv. (1910) pp. 23-7 (5 figs.). 

 || SB. k. Akad. Wiss. Wien., cxviii. (1909) pp. 943-65 (1 pi. and 2 figs.), 

 ^f Proc. Seventh Intemat. Zool. Congress, 1907 (published 1910) 5 pp. 

 ** Journ. Coll. Sci. Univ. Tokyo, xxvii. (1910) art. 10, pp. 1-19 (4 figs.). 



