482 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Nematohelminthes. 



Life-history of Onchocerca." — W. Xicol discusses the life-history 

 of this parasite, which causes nodular disease in cattle in Australia. The 

 facts point to the Breuil's conclusion that the larvae penetrate the skin 

 and emerge in water. From excised nodules the larvae emerged in 

 large numbers for some time after the death of the host. They make 

 their way through the capsule, and infection may be water-borne. On 

 the other hand, when the larva} are near the surface of the skin, they 

 might be very readily ingested by any biting insect, such as cattle-fly 

 or mosquito — a view that has been repeatedly suggested. 



Platyhelminthes. 



New Species of Amphilina.t— T. Southwell reports on Amphilina 

 magna sp. n., one of the primitive Cestodarian tapeworms. It occurred 

 in the body-cavity of a marine fish, Diagramma crassispinum, and was 

 of unusual dimensions, 250 mm. in length by 12 mm. in breadth. 



Structure of Amabilia.ij: — F. E. Beddard discusses some peculiari- 

 ties in the structure of Amabilia lameUigera. The head was so com- 

 pletely retracted that there was no external sign of its existence save a 

 slit-like gap anteriorly. It is hardly more than an eighth of a milli- 

 metre in breadth, and cannot be an effective anchor for the unwieldy 

 body. The longitudinal muscular layer of the body is continued into 

 the lateral outgrowths of the proglottids, which are characteristic of the 

 family Amabiliidae. A transverse section of these appendages shows 

 strands of muscle passing from side to side, and considerable movement 

 must be possible. It may be that the worm is able to fix itself to the 

 wall of the intestine more securely by means of these appendages, as 

 well as to move from place to place, and their existence, as functional 

 parapodia, may supplement the feeble scolex. 



The water-vascular or excretory system consists of a median stem 

 opening by a pore both dorsally and ventrally, of two transverse vessels 

 on each side connecting this with two lateral longitudinal vessels, one 

 lying above the other ; these communicate at the orifice of the transverse 

 vessels ; there is no network of small tubes. Beddard calls attention to 

 the likeness shown by the vertical, radiating and lateral tubes to the 

 canal-system of a Ctenophore. 



The testes are in one or two horizontal rows, four to six deep, 

 disposed in two groups separated by ovary, rarely forming a continuous 

 row. The cirrus-sacs are large and muscular, two in each proglottis. 

 The opening is on each side between the lateral water-vessels and dorsal 

 to the nerve-cord. The cirrus is armed with numerous spinules. The 

 •.as deferens is short, without a coil, opening into an oval vesicula 

 seminalis connected by a short duct with the cirrus-sac. The ovary is 



* Rep. British Assoc, Australia, 1915, pp. 407-9. 

 t Bull. Dept. Fisheries Bengal, No. 5 (1915) p. 32. 

 % Proc. Zool. Soc, 1915, pp. 175-91 (8 figs.). 



