186 SUMMARY OF CURRENI RESEARCHES RELATING TO 



of their insignia. The genus Litistowia is restricted to Marsupials and 

 Monotrernes ; its exclusive occurrence in American and Australian 

 Aplacentalia points to a remarkable similarity in the parasitic fauna of 

 the autochthonous inhabitants of the two continents. 



Parasites of Ural Birds.* — "W. Clerc collected 408 birds from the 

 Ural, and found parasites in 246. In 233 there were Cestodes, repre- 

 senting 57 species, of which ten are new. Nine species of Nematodes, 

 three of Acanthocephala, and eight of Trematodes were also found. 

 The present memoir contains descriptions of the Cestodes. 



Incertee Sedis. 



Lohmannia catenata g. et sp. n.f — E. Neresheimer found in the 

 gonadial cavity of FriUllaria, a remarkable mesozoon parasite. It 

 consists of an anterior portion with branched pseudopodia, and a chain 

 of segments without pseudopodia. There is but one layer of cells, and 

 the boundaries are not very clear. The anterior nuclei are larger 

 than the rest and otherwise different. To each of them a pseudopodium 

 seems to be associated. 



The young form is like a gastrula, and diploblastic. The internal 

 layer grows actively, and the external layer is reduced to delicate mem- 

 brane except at the anterior end, where the nuclei are associated with 

 the pseudopodia. The segments formed by the internal body are 

 liberated, bursting the outer membrane, and the anterior region then 

 forms new ones. 



Rotifer a. 



Excretory Organs in the Family Melicertidae.J — Stan. Hlava 

 has studied these in Lacinularia socialis, Megalotrocha albojlavicans, 

 Melicerta ringens, and Limnias ceratophylli, and finds that these organs 

 conform essentially to the same plan which has been known in 

 Asplanchna. The paired thick-walled lateral canals, forming com- 

 plicated knots in the head region, are accompanied on each side of the 

 body by a fine thin-walled tubule which alone bears the vibratile tags, 

 of which there are five on each side. The two thick-walled canals 

 unite posteriorly into a single short tubular piece which corresponds to 

 the contractile vesicle of other rotifers, but which has no power of 

 contraction. Valentine's statement that this tube opens outward by 

 an independent poms in Lacinularia is not confirmed. The narrow 

 thin-walled tubules, bearing the tags, open into the thick-walled canals 

 in two places — in the twisted knot in the head, and posteriorly just 

 before these canals unite. The thin-walled tubules give off small 

 branches bearing the flame-cells at their ends. An additional feature 

 in Lacinularia and Megalotrocha is a fine connecting tubule between 

 the two sides in the corona. In addition to the flame-cells the author 

 has observed three fine vibratile cilia within the lumen of the thick- 

 walled canals in Lacinularia and Megalotrocha. 



In the same note the author establishes a new genus, Conochiloides, 



* Rev. Suisse Zool., xi. (1903) pp. 241-368 (4 pis), 

 t Biol. Centralbl., xxiii. (1903) pp. 757-00 (3 figs. . 

 J Zool. Anzeig., xxvii. (1904) pp. 247-53(4 figs. 



