696 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Annelids, especially as regards the ccelom and genital organs. There 

 is no possibility of derivation from Platykelminths or Trochozoa, but 

 there may be some connection with a Scyphozoon-like ancestral type. 

 The completely segmented type of body has arisen from a state with 

 " pseudornetamerism " including gonomerism, which began in the 

 common ancestors of the Gordiidse and the free-living Annelids, 

 either independently or in direct connection with the cyclomeric gonads 

 of Scyphozoa. The segmentation of the mesoderm arose in dependence 

 on gonomerism ; while neuromerism and external segmentation are to 

 be regarded as locomotor adaptations. 



Monograph on Acanthocephala of Birds.* — L. de Marval follows 



Hamann in recognising three genera — Echimrhynchus, Gigantorhynchiis, 



and Neorhynchus ; he has studied as far as possible for each species, (1) 



the form, dimensions, musculature, and subcutaneous canals ; (2) the 



form, size, and structure of the eggs; (3) the form and dimensions of 



the " cou " and " faux-cou " ; (4) the rostrum and its hooks. He deals 



with 32 species, all of Echinorhynchiis, except Gigantorhynchiis com- 



pressus Rudolphi, G. mirabilis de Marval, and Neorhynchus hemignathi 



Shipley. 



Platyhelminthes . 



Copulation in Cestodes.f — C. v. Janicki describes Bertia rigida sp. n. 

 from a species of Phalangista, and Cittotcenia zschokkei sp. n., both from 

 New Guinea. In studying the latter, he found that there is, as the 

 proglottis grows older, an atrophy of the vagina. The facts which he 

 describes lead him to the interesting conclusion that in the copulation 

 the younger proglottides are passive, being practically female, with the 

 testes still undeveloped, while the mature proglottides, though the female 

 organs are in full development, function as males, the absence of a 

 vagina preventing normal reception of sperms. Thus all the ova in the 

 ripe joints are fertilised by sperms received in youth in the large recep- 

 taculum seminis. There is no direct communication between the testes 

 and the receptaculum seminis of the same proglottis, so that internal 

 autogamy is out of the question. The insemination of the immature 

 joints of a young strobila, which has no ripe joints, must of course be 

 effected from another older strobila. 



New Cestode Larva Parasitic in Man.J — Isao Ijima describes 

 under the title Pier ocerco ides prolifer g. et sp. n. the larva of a Bothrio- 

 cephalid (?) found in enormous numbers, especially in the subcutaneous 

 tissues, in a woman from Tokyo. Most of the worms were in capsules, 

 a few were free. The worm has the power of dividing and multiplying 

 within the capsule, and it can also proliferate by budding. It shows 

 a far-reaching structural agreement, especially in the musculature and 

 excretory system, with the Bothriocephalid larva Sparganum of Diesing, 

 as well as with Cobbold's " Ligula mansoni" 



Maturation, Fertilisation, and Development in Zoogonus mirus.§ 

 R. Goldschmidt has studied this Distomid found in the hind-gut of 



* Rev. Suisse Zool., xiii. (1905) pp. 195-387 (4 pie.). 



t Zool. Anzeig., xxix. (1905) pp. 127-31 (2 figs.). 



X Journ. Coll. Sci. Univ. Tokyo, xx. (1905) Art. 7, pp. 1-24 (1 pi.). 



§ Zool. Jahrb. xxi. (1905) pp. G07-54 (3 ph. and 1 fig.). 



