ZOOLOGY AXU BOTANY, MICKOSCOPY, ETC. 61 



Ampullaria, common in tlie Philippine Islands. It is a voracious 

 organism, like a miniature l)alloon, moving evenly and gracefully with a 

 slight rotary motion, but assuming varied shapes (like anKXibie) when 

 under constraint. The most remarkable feature is the enclosure of the 

 micronucleus within the megaimcleus. Its normal position is at the 

 concavity on one side, but it may be actually enclosed. At other times 

 it may wander out into the cytoplasm. The actual enclosure may imply 

 a type of nuclear division of a rather new and remarkable kind, or a 

 process of nuclear re-organization comparal)le to endomixis. The anterior 

 end of the animal is a blunted cone, excavated ventrally into a funnel, 

 at the base of which there is the cytostome with a ciliated cytophaiwnx. 

 There are two well-defined contractile vacuoles. J. A. T. 



Trypanosoma associated with Fatal Disease in the Carabao. — 

 Frank G. Haughwout and STAXTO>f YouxGBEiiG {Philippine Journ. 

 Sci., 1920, 16, 77-87, o pis., 2 figs.). A male Philippine carabao, 

 which died with severe haemorrhage, hsematuria and other symptoms, 

 showed polymorphic trypanosomes which were nearer to Trt/panosoma 

 theihri than to other forms. A description is given of the form, which 

 by reason of its large size and certain peculiarities in the relations of 

 nucleus and parabasal b )dy is well suited for cytological study. A 

 watch must be kept for the recurrence of this trypanosome. J. A. T. 



Strombidium viride. — E. Pexard {Revue Suisse Zool., 1920, 28, 

 1-9, 9 figs.). As in 8. mirabile there is in S. viride a cuirass of very 

 minute hexagonal plates. The peristome shows a crown of ten to eleven 

 strong membranellae. The cytoplasm is filled with zoochlorellte and 

 trichocysts which can be made to ':'xi:)lode. There are two very minute 

 micronuclei beneath the large spherical or ovoid macronucleus. There 

 are no true contractile vacuoles, but there are vacuoles in connexion 

 with an annular equatorial canal, and this canal is in relation with a 

 special tube or canal issuing from the depth of the peristomial depression 

 and pursuing a somewhat intricate " figure eight " course. This has to 

 do with the formation of a new individual by a process like internal 

 budding. This interesting Infusorian is found among plants in the 

 clear water of ditches, but it is not common. J. A. T. 



Vitality in Infusorians. — Gary X. Calkins {Journ. Exper. Zool., 

 1920, 31, 287-:-!05, 1 chart and 2 diagrams). It has been shown that 

 [■roUpfus mobilis after conjugation has an initial optimum vitality which 

 gradually diminishes with age until the protoplasm finally decays from 

 the exhaustion of metabolic activities. An analysis of seventeen series, 

 all representing the same original protoplasm, shows that the differences 

 between them as regards vitality are due to the age of the parents at the 

 time of conjugation, or rather, to differences in vitality at different 

 periods of the life-tistory. All series with an extremely low vitality 

 come from parents which were in the period of old age at the time of 

 conjugation. All series with high vitality, on the other, hand, came 

 from parents in the period of youth at the time of conjugation. So far as 

 the experiments have gone. there is no evidence that continued in-breed- 



