18 
Ohservations on British Rat-Jieas 
DugJ:s (1910). Ann. Set. Nat. xxvii. 160. 
Heller (1896). E7it. Nadir, xxit. 97, figs. 1 and 2. 
Indian Plague Commission (1906). Joiirn. of Hygiene., vi. 446. 
- (1907). lUd. VII. 429, 445. 
- (1908). Ihid. VIII. 295. 
- (1910). Ihid. X. 460. 
Kolenati (1862). Horae Soc. Ent. Ross. II. 27. 
Linnaeus (1746). Fauna Suecica, Edit. I. 
Martin and Rowland (1911). Reports of Local Government Board on Public 
Health and Medical Subjects, N.S., No. 52. 
Raids (1710). Historia insectoimm. 
Rothschild (1898). Ent. Rec. and Journ. of Vai-iution, ix. 65. 
- (1900). Nov. Zool. VII. 542. 
- (1902). Ent. Monthly Magazine, xiii. 225, pi. iv. 
- (1908). Parasitology, i. No. 1. 
ScHRANK (1803). Fauna bonica, ill. 195. 
Tiraboschi (1904). Arch, de Parasitologic, viii. 161. 
Wagner (1898). Horae Soc. Ent. Ross. xxxi. 35. 
II. REPORT ON RAT-FLEAS IN CAMBRIDGESHIRE. 
By GEORGE H. F. NUTTALL, F.R.S., 
AND C. STRICKLAND, M.A. 
The following record relates to fleas collected from rats in and about 
Cambridge during the period 3rd March, 1909, to 20th November, 1911. 
We had difficulty in obtaining rats in Cambridge during the year 1911 
owing largely to the high price asked b}^ professional rat-catchers 
who usually sell them for sporting purposes. We have, consequent!}', 
included data collected by us during the two years before this investi¬ 
gation was undertaken on behalf of the Local Government Board. 
With regard to the species of fleas collected from the rats, by far 
the larger numbers were G. agyrtes, especially in the case of the rats 
captured at Cherryhinton Brook. A few G. fasciatus and but one 
specimen each of P. irritans and G. bisoctodentatus were found on the 
rats. The largest numbers of fleas per rat (G. agyrtes) were captured 
in February and March. 
