Department of Fisheries Bengal and Bihar & Orissa Bulletin No. 11. On Hilsa Investigation in Bengal and Bihar & Orissa

No definite efforts towards the elucidation of the variousjmportant problems connected with the habits and the general lifhistory of Hilsa were made owing to the limited nature of the Hilsa season and further the very inadequate staff of the department. [...] The investigations made by the department up to the end of the Hilsa season of 1916 have been described in dtail elsewhere (8) and may here be summarised under the following two heads :— (1) Distribution and habits.---A survey was made with the object of ascertaining the distribution of Hilsa in the rivers of the Gangetic plain and a map prepared showing the limits of distribution. [...] Chaudhuti (2) states that the occurrence of Clupea ilisha in the Lake throughout the year and the fact of its not dying off immediately after capture as well as the comparative freshness of the water of the Lake soon after freshets should prove to be sufficient"5 inducement to practical piscictilturists to attempstriping of Clapea ilisha in the Lake though it must remain doubtful if the [...] Moreover owing to the 'force of the current. the mud gradually begins to settle down at the bottom of the jar and the eggs becoming embedded in it do not rotate properly ; the essential lea cure of the Macdonald jars is continual movement of the eggs.; and this cannot be produced because the eggs instead of being in a regular state of motion in the water become covered with particles of mud [...] As the fungus developed and absorbed the food material in the eggs the eggs became flaccid and the water-space decreased as a result of which the zona-radiata instead of being a tense membrane on the surface of the eggs became wrinkled and shrivelled up.