508 NOTES ON SOME PARASITIC PROTOZOA, 



almost bidden by tbe number of bacteria present. Tbe spire- 

 chaetes are very small and delicate, with 2 or 3 spirals, sometimes 

 regular, at other times A'ery irregular in their windings, with 

 apparently blunt ends, and usually about 2-5/Lt long, though 

 occasionally somewhat longer. 



Dr. Max Liihe,(7) in Mense's " Handbuch der Tropenkrank- 

 heiten," (iii. 1906, p. 184), mentions that spirochaetes have been 

 observed in the stomachs of various animals, such as dogs, cats^ 

 and " Wanderratte" [Mus decuinanus). The number of windings 

 is usually 9 to 11, but may be between 2 and 24. This wide 

 variation suggests that the spirochaetes we have met with in the- 

 csecal contents are of a different species whose size is more con- 

 stant. As tliey have so far been met with more frequently in 

 Mus ratlus, we propose the provisional name of Spirochaeta ratti 

 for them, for convenience in future reference. 



The presence of these spirochaetes in rats is of special interest^ 

 in view of the discovery some while ago of spirochaetes in 

 malignant tumours of rodents. Quite recently, these bodies have 

 been found to be in no way etiologically related to the tumours,, 

 but accidental associations. 



Rounded Bodies, possibly Protozoal, in the 

 Blood-Corpuscles of a Leather-jacket Fish 



(J/ n a c a n t hu s sp.). 



(PI. xlviii., %:. 12-13.) 



In smear-preparations of the blood of a fish known as a Leather- 

 jacket (Monaca7iihus sp.) obtained at Broughton Island off Port 

 Stephens, N.S.W., by the Director in 1907, and handed to us for 

 examination, many of the corpuscles contained rounded, usually 

 quite circular bodies of various sizes from OSfx to I'Oyut in diameter, 

 situated close to but quite separated from the nucleus of 

 the cell. There was a marked contrast in the staining reactions 

 by Giemsa's method between these bodies, the nucleus of the 

 host, and the protoplasm of the host. The latter assumed 

 a greenish-blue tint, the nucleus a deep blue, and the bodies a 



