36 SUMMARY OF CURRENT RESEARCHES RELATING TO 



tractile cortex and an internal protoplasmic substance with the nucleus. 

 The cortex consists of fibrils and interfibrillar substance, and the fibrils 

 consist of finer fibrils. Usually the shape is fusiform, but there are 

 various departures from the type. Muscle-bridges occur especially in 

 the intestinal musculature. Many interesting details are recorded ; thus 

 in the muscle-cells of the dorsal blood-vessel of Pontobdella, the con- 

 tractile cortex shows circular striping externally, while the internal 

 striping runs in the longitudinal direction of the blood-vessel. 



Sagitta enflata.* — Paul Hallez discusses the characters of a species 

 of Sagitta common at Portel, which he refers to 8. enflata Grassi, though 

 it has a smaller and more slender body, with never more than five 

 anterior teeth, and with the ventral ganglion nearer the anterior fin. 



Nematohelminthes. 



Studies on Nematodes.!. — 0. von Linstow describes Hedruris 

 squamata sp. n. from the stomach and intestine of the Chelonian, 

 Clemmys guttata. 



New Nematodes.^ — 0. von Linstow describes the following new 

 species from German S.W. Africa : Heteralcis schebeni, from the intestine 

 of Gynktis penicillata ; H. poculum, from the francolin ; Physaloptera 

 brevkauda, from the same ; and Oxyuris polgoon, from Xerus setosas. 



Ascaris mystax in Lion.§— G. Vallillo reports the abundant occur- 

 rence of this species in the mucous membrane of the stomach and 

 intestine of a lion. Only one previous case has been recorded (Linton). 



Structure and Life-history of Rhabditis brassicae.|] — Rowland 

 Southern describes this new species of Nematode from a rotten turnip. 

 The two sexes were found in approximately equal numbers, but the 

 " females " are really self-fertilising, protandrous hermaphrodites. The 

 species may be in process of transition to a dioecious condition. All 

 stages between oviparity and viviparity occur, but the latter is rare. 

 The evidence goes to show that Rhabditis brass icse does not originate 

 disease, though they quickly destroy the turnips if they get into the soft 

 tissues through an injury to the epidermis. 



Trichinosis in Posen.lf— Otto Busse found in Posen that in 96 

 bodies of people over sixty, no fewer than 18 showed encapsuled 

 Trichinae — that is, about every fifth. He shows in an interesting 

 indirect way that the parasites may remain living within their capsules 

 for more than forty years. 



Microfilariae of Fowl.**— C. Mathis and M. Leger find that in the 

 fowls at Tonkin there is an abundance not only of Microfilaria mansoni, 

 but also of another species which they record as M. seguiiii sp. n. 



* Arch. Zool. Exper., ii. (1909) Notes et Revue, No. 2, pp.xxix.-xxxiii. (5 figs.). 



t Arch. Naturges. lxxv. (1909) pp. 63-6. 



X Centralbl. Bakt. Parasitenk., 1. (1909) pp. 418-51 (4 figs ). 



§ Op. cit., Ii. (1909) pp. 461-2. 



fi Journ. Econ. Biol., iv. (1909) pp. 91-5 (1 pi.). 



«j[ Centralbl. Bakt. Parasitenk., lii. (1909) pp. 368-77. 



** C.R. Soc. Biol. Paris, lxvii. (1909) pp. 407-9 (1 fig.). 



