268 



HARDWICKE'S SCIENCE-GOSSIP. 



May 6th. — Moulted again, and also on the follow- 

 ing dates: May 12th, May 17th, May 23rd, and 

 May 27th. Six changes in less than a month. Jurine 

 made a similar observation, and found that between 

 April 12th and May 18th five moults had been 

 undergone. 



After the last moult of the one I had under 

 observation, another deposition of eggs took place, a 

 batch of twenty (there may probably have been more, 

 I am not certain) this time, without the intervention 

 of the male. This procedure was followed by a 

 period of lethargy. I then turned my attention to 

 the young. When they are born they are exactly 

 like their parent and by a series of moults gradually 



I made many other experiments to the same end, but 

 noticed that after the first batch the rule did not hold 

 good and reproduction was at a stand-still. I am 

 still engaged on the same subject and have purposely 

 refrained from saying much here, as it is one that 

 deserves a whole article to itself. 



In summer, when the pools dry up, they bury 

 themselves in the mud, where they remain until the 

 welcome rain once more gives them freedom. Miiller 

 and Strauss say that the greater number of non- 

 parasitical Entomostraca live upon vegetable and not 

 upon animal matter, and the former states that while 

 keeping a number of species of Daphnia, Cypris, 

 Cyclops, etc., the water in which they were kept 



^/frt*Vtu^t.'9 z 



fig. 154. — 1, C. iristriata: a, superior antenna; B, inferior antennae; c, first pair of legs; 2, first pair of jaws ; A, row of 

 nineteen spines ; n, branchial lamina ; c, basal plate ; 3, second pair of jaws ; 4, mandibles ; 5, first pair of legs ; 6, second 

 pair of legs. (All greatly magnified.) 



attain adult size. Many observers, however, state 

 that the young Cypris undergoes metamorphoses ; 

 but I must confess I have never been able to dis- 

 tinguish them as yet, and until I do, must necessarily 

 have the opinion my own eyes warrant me. 



Desmaret, an excellent observer, also avows that 

 they do not undergo metamorphosis, but present on 

 their exclusion the identical appearance miniatured, 

 they are to preserve throughout life. 



The first batch of eggs my Cypris deposited I 

 solated for the purposes of studying the development 

 within the egg itself, and was surprised later on to 

 find that the females reproduced their kind freely. The 

 ova, young and adults, had been rigorously kept apart, 

 and the intervention of a male was quite impossible. 



evaporated from five inches to one inch. He sub- 

 jected at various times dips from this water to a 

 thorough microscopical examination, and found not 

 the slightest trace of animalcu!ae, though the intestines 

 of the Entomostraca were full, thus proving that they 

 had not fasted. 



I have always found the Cypris very carnivorous, 

 and in fact could not keep them in the same vessel 

 with other species of Entomastraca, and have been 

 unable to keep them any appreciable length of time 

 without a supply of animal matter. When I have 

 done so, they have gradually become lighter in colour 

 and almost transparent, until at last they became 

 languid, and would allow a dipping-tube to.be placed 

 in close proximity to them without showing the 



