ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 485 



Talitriis, except for the tifth side-plate, the antennule sUghtly shorter 

 than the peduncle of the antenna, the presence of a fourth joint on the 

 inaxillipede palp, the first gnathopod not so long as the second and 

 not stronger, and with a strong swollen fifth joint. The fact that this 

 Amphipod thrives in the streams of the Woodbush suggests that some- 

 thing might be done for trout by increasing its numbers and range. 



Relict Forms of Mysis.*— Sven Ekman describes from fresh-water 

 a variety (f. malarensis) of the marine Mysis mixta Lilljeborg. He 

 thinks that it owes its peculiarities to its new habitat. Convergent 

 changes are to be seen in M. oculata f . relicta, which is a similar relict 

 variety. A similar relation exists between Gamaracanthus lacustris 

 G. 0. Sars and G. loricatus (Sabine). Other relict forms of North 

 European fresh-water basins are Pontoporeia affinis Lindstrom and 

 Limnocalamis macrurus G. 0. Sars. 



Two New British Entomostraca.f — G. Stewardson Brady describes 

 Diaptomus pusilhis sp. n., from Loch Ness, off Drumnadrochit, and 

 Anmella sui salsa g. et sp. n., from slightly brackish water by the side of 

 the River Arun, near Arundel. The latter is like Candona, except that 

 there are three pairs of ambulatory legs in addition to the flexible fourth 

 pair, which is contained within the shell. There is also a remarkable 

 pair of setiferous appendages arising from the ventral surface of the 

 body, probably near the base of the first pair of legs. These appendages, 

 possibly homologous with the " processus piliferus " described by G. 0. 

 Sars in Bairdia subdeltoideay is hispid, and so are the anterior legs. Also 

 noteworthy is the presence of a pair of rod-like sensory appendages on 

 the ante-penultimate joint of the antennae. The animal has apparently 

 lost all its swimming powers. 



Transmission of Environmental Effects on Simocephalus vetulus.J 

 W. E. Agar has studied an abnormality — reflexion of the valves of the 

 carapace — in this Daphnid, which seems to be induced by the nature of 

 the food ingested. Affected animals appear quite healthy and reproduce 

 freely. He found that although individuals were removed to control 

 conditions (of relative normality) before the eggs were laid, the young 

 developing from these eggs exhibit the same abnormality as that which 

 their parents had acquired during their ontogeny, as a direct result of 

 their environment. This result has been confirmed over and over again. 

 Females with ripe eggs were also removed from control conditions and 

 put into the particular culture which induces reflexion of the valves. 

 The young developed from these eggs were fully normal, showing the 

 persistence of the effects of normal environment. Subsequent broods of 

 these females in the culture became successively more and more reflexed, 

 i.e. the normality wore off just as the abnormality also does. 



In a second set of experiments, by raising the temperature (to 

 28 -5° - 31 • 5^ C.) the size of the young Daphnids was greatly reduced in 

 their first, and indeed in all instars. The rate of the life-cycle was also 



* Internat. Rev. Hydrobiol., v. (1913) pp. 540-50 (6 figs.). 



t Proc. Zool. Soc, 1913, pp. 231-4 (3 pis.). 



X Phil. Trans., Series B, cciii. (1913) pp. 319-50. 



