36 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Nematohelminthes. 



North American Fresh-water Nematodes.*— X. A. Cobb has 

 done a useful piece of work in giving an account of the North American 

 free-living fresh-water Nematodes. A [nut from bis own previous 

 investigations he has had an almost unworked held, and many new 

 forms have been discovered. He deals with 2* species, but no doubt 

 there is a horde of species awaiting discovery in Xorth American waters. 

 As in former papers, he makes much use of measurements of the worm 

 viewed in profile ; the first from the anterior end to the base of the 

 pharynx, the second to the nerve-ring, the third to the "cardiac con- 

 striction " or end of the neck, the fourth to the vulva in females and to 

 the middle of the body in males, and the fifth to the anus. 



s 



Classification of Strongylidas.f — M. Neveu-Lemaire discusses the 

 proposal of Railliet and Henry to divide the genus Nematodirus into 

 tw r o sub-genera — Nematodirus with the type Slrongylus filicolUi 

 (Rudolphi, 1802"), and Mecistocirrus with the type Strongylus digitatus 

 von Linstow, 1906. The author gives a good figure of the female 

 genital system in the two types, and shows that the sub-genera must be 

 regarded as genera. . In Nematodirus filicollis the vulva is towards the 

 posterior third of the body ; the vagina is very short ; the ovijectors are 

 well-developed ; one of the uteri runs posteriorly, the other anteriorly i 

 there are only a few large ova, their diameter equals that of the uterus ; 

 the ovaries are short, the anterior one extending towards the head, the 

 posterior one extending first backwards to the tail and then forwards. 

 In Mecistocirrus digitatus the vulva is posterior, a little in front of the 

 anus ; the vagina is very long ; the ovijectors are slightly developed ; 

 the two uteri are side by side, extending anteriorly, and containing a 

 considerable number of ova, small in proportion to the dimension of the 

 animal ; the ovaries are long and parallel, and describe circumvolutions 

 around the alimentary canal. 



Ankylostomiasis in Dogs.J — W. Nicoll finds that the hook-worm 

 anaemia of dogs differs from that of man inasmuch as only young 

 animals suffer greatly, and the progress of the disease to a fatal termina 

 tion is very rapid. Older dogs are infected only to a moderate extent, 

 there is a minor degree of anaemia, and there is gradual recovery. The 

 anaemia in young dogs is characterized by great loss of weight, emacia- 

 tion, prostration, and intestinal haemorrhage. The blood volume of dogs 

 suffering from the minor degree of hook-worm anaemia is not materially 

 altered, but if anything is somewhat diminished. The oxygen capacity 

 of the blood per unit of body-weight is also, on the average, somewhat 

 decreased. Infection is generally accompanied by distinct though not 

 profuse haemorrhage, which is most marked in the early stages, but 

 tends to disappear. Eosinophilia was not a constant sign either of 



* Trans. Amer. Micr. Soc, xxxiii. (1914) pp. 69-119 (7 pis.), 

 t Bull. Soc. Zool. Fiance, xxxix. (1914) pp. 293-6 (2 figs.), 

 t Journ. Hygiene, xiii. (1914) pp. 369-92. 



& 



