JOURNAL 



OF THE 



ROYAL MICROSCOPICAL SOCIETY. 



OCTOBEE 1889. 



TEANSACTIONS OF THE SOCIETY. 



IX. — Description of a New Species of MegcdotrocTia. 

 By Surgeon V. Gunson Thorpe, R.N. 



{Read 12th June, 1889.) 

 Plate XII. 



During the years 1886-9, whilst serving on board H.M.S. ' Paluma,' 

 employed in the survey of the waters between the east coast of 

 Queensland and the Great Austi-alian Barrier Eeef, many opportunities 

 were afforded me for the study of microscopic life, both fresh-water 

 and marine. Whilst the higher forms of both the fauna and flora of 

 Queensland are being very thoroughly worked out, this branch of 

 natural history has been almost if not quite untouched. This fact 

 stimulated me to devote my leisure moments to the study of the 

 microscopic life of the colony, and especially to that of the Eotifera. 



The localities in which llotifera are to be found in Queensland are 

 few and far between ; water, except at certain times of the year, being 

 scarce in that tropical climate. In May, soon after the rainy season, 

 one occasionally comes across, in the midst of the dense Australian 

 bush, a charmingly secluded little pond, shaded on all sides by 

 Eucalypti, grass-trees, and acacias, with Idles, ferns, and orchids 

 growing in great profusion around ; brightly coloured dragon-flies 

 and other insects flitting across its surface ; parrakeets and cockatoos 

 screaming overhead. The water of such a pool teems with various 

 species of Floscularia, with Melicerta conifera and ringens, Limnias 

 anntdcdus, Brachionus militaris, and many other kinds. Three 

 months afterwards, the same place may be found completely dried up, 

 and the ground fissured in all directions by the fierce heat of the sun ; 

 and yet, in the following year, the same locahty is as prolific as ever. 

 Again, in marked contrast, at another time one meets with a tiny 

 pool, not more than three or four feet across, on the bleak and rocky 

 headland of an island out at sea, exposed to the storm and to the 



EXPLANATION OF PLATE XII. 



a, dorsal surface; h, ventral surface; c, side view; d, corona contracted; e, view 

 of head from above ; /, mastas ; g, male. 



1889. 2 u 



