1916.] The Third Indian Science Congress. cxv 



call it, the renal cardinal meshwork, is the characteristic of an imperfect 

 kidney which being unconcentrated and yet bulky has had to encroach 

 upon the lumen of the posterior cardinal vein in order to develop. In 

 the active bird the femoral veins have resisted kidney encroachment to a 

 large extent owing to the volume of blood to be returned to the heart and 

 therefore only the smallest traces of a renal cardinal meshwork remain : 

 in the Mammal, the kidney has become in the highest types very concen- 

 trated, the tubules being arranged so as to open into the ureter in the 

 most convenient way possible, it has shifted outwards and forwards and 

 by its peculiar abbreviated development has kept clear of the vein^ 

 altogether. 



Seasonal Conditions governing Pond Life in the Punjab. — By 



Batni Pebshad. 



The seasons in the Punjab are quite different from those in Bengal 

 and other parts of India, and it was with a view to ascertain the effect 

 of the seasons on the pond- life that the work was begun. It was found 

 that animals like Hydra, Spongilla and Australella, do not nourish in 

 winter which is very severe, but during the latter part of summer — 

 summer and winter being the only well-marked seasons in the Punjab, 

 spring and autumn being short and ill-defined. During winter all these 

 forms die, having developed resistant bodies like spiny eggs, gemmules or 

 statoblasts for the preservation of the species. 



In the case of Daphnia winter-eggs are formed at the beginning of 

 winter. In the ease of insect larvae like those of Chironomus and Ano- 

 pheles, it was found that in winter the period of larval life is much 

 prolonged and that they are very inactive. 



The Aortic Ligament in Fishes. — By D. R. Bhattacharya. 

 Notes on Elasmobranch Blood Cells.— By R. H. Whitehouse. 



The history of the red blood cells is interesting in consideration of 

 the following points. It seems most likely that they are produced 

 through life in the spleen. Young cells are characterized by their 

 comparatively large nucleus with widely separated chromatin and the 

 very small envelope of cytoplasm which is basophile in ita reaction. 

 Haemoglobin is acquired comparatively late in development and when 

 adult the nucleus occupies about J the length and breadth of the cell, is 

 compact and has an irregular outline. Frequent " Kernbrucken " or 

 nuclear bridges were observed which corresponded to the structures 

 described by Stauffacher and Knall in a variety of other cells. The 

 disintegration of the cell begins by a basophile degeneration of the cyto- 

 plasm spreading from the nucleus radially and finally producing a struc- 

 ture much resembling a haemamaeboid parasite, and it was suggested that 

 alleged cases of such parasites invading cells and causing the nucleus to 

 be ejected should be revised for fear in reality they were only cases of 

 basophile degeneration of the erythrocyte. 



The leucocytes are of the usual type and show the eosinophilous 

 forms to great advantage. •' Kernbrucken " are also to be observed here. 



The Indian Varieties and Races of Turbinella pyrum (Linn). — 



ELL 



In this paper it was shown that the Indian representatives of the genus 

 Turbinella are limited to a single species — T. pyrum (Linn.). The species is 

 not an ideal one composed of a single predominant form : but must be consi- 

 dered a well-marked example of the collective species, as it comprises at 



