n04 ]Mi-. E. T, Browne on the 



The liabits of the species of Pycnosoma are similar to tliose 

 of tlie well-known "green-bottle flies'^ {Liicilia), and there 

 can be little doubt that P. vrarginah and P. chloropyga, in 

 addition to Musca doniestica, L., were partly responsible for 

 the spread of enteric fever among the British Army during 

 the late war in South Africa*. 



British Museum (Natural History), 



Cromwell Koad, S.W. 



Jau. 30, 1906. 



XXXIX. — On the Freshwater' Medusa Limnocnida tanganicse 

 a7id its Occurrence in the River Niger. By Edward T. 

 Browne, Zoological Research Laboratory, University 

 College, London. 



In the collection brought back by the late J. S. Budgctt 

 from the delta of the Niger in 1903 there were, five specimens 

 of a Medusa taken in a fresh water lagoon near Assay, on the 

 Forcados River, one of the western branches of the Niger, 

 and about 102 geographical miles from the sea. Tlie occur- 

 rence of a Medusa in the Niger was, however, first noticed 

 by Dr. Tautain in 1 888. He caught specimens near Bamakou, 

 in the French Soudan, but tailed to i)reserve them. As he 

 was nnable to carry out his intention of obtaining a iresh 

 su])ply, a description of tlie JMedusa was never published, 

 but only the fact of its occurrence (i). 



The Medusa found by Budgett is, I am sure, Limnocnida 

 tanganicce, Bohm. It has, however, many more tentacles 

 and sense-organs than are mentioned by Giiiither (2) in the 

 original description of the s[)ecies, and it comes nearer to the 

 description given by Gravier (3) of the specimens found in 

 the Victoria Nyanza. 



The ipresence oi Li'mnoctiida tanganicce in the Niger is, I 

 thiiik, more interesting than the discovery of a new fresli- 

 \\ater species, as the Medusa is found in a river far away 

 from the Great African L;ikes. 



The occurrence of freshwater Medusas in a river which has 

 direct communication with the sea naturally suggests the idea 

 that the Medusa} have gradually migrated up the river and 



* See E. E. Austen, " The House-Fly and certain Allied Species as 

 Disseminators of Enteric Fever among TroojjS in the Field," Journal of 

 the Royal Army Medical Corps, Jui.e 1904, pp. 1-16, pis. i. & ii. 



