JOURNAL 
OF THE 
ROYAL MICROSCOPICAL SOCIETY. 
JUNE 1891. 
TRANSACTIONS OF THE SOCIETY. 
IV . — New and Foreign Botifera. 
By Surgeon Y. Gunson Thorpe, K.N., F.B.M.S. 
( Read 15 th April, 1891.) 
The Male of Trochosphaera aequatorialis. PL VI. fig. 1. 
For more than thirty years this rare rotifer has, I believe, eluded 
rediscovery since Professor Semper first found it in the Philippine 
Islands. In January 1889, I had the good fortune to find it once 
again in the Fern Island pond of the Botanical Gardens, Brisbane, 
Australia. Here it was in company with enormous numbers of 
Volvox globator, and the resemblance it bore both in shape and size to 
these algae, as the spherical rotifers and the moving plants circled 
in and out amongst each other, irresistibly caused one to consider 
whether we have not here an instance in the microscopic world of 
“ protective mimicry.” The time at my disposal for the examination 
of this remarkable genus was little more than a week, but during this 
period I was lucky enough to witness the birth of the hitherto 
unknown male. The male rotifer appeared to lie free in the body- 
cavity of the female, partially encircled by the intestinal tract 
(fig. 1 a). Nevertheless it was probably surrounded by the invisible 
wall of the oviduct. During the progress of labour the mother roti- 
fer was perfectly quiescent, and indeed she never recovered vitality. 
EXPLANATION OF PLATES VI. & VII. 
Trochosphaera aequatorialis. — Fig. 1 a. Unborn male in body of female. 1 h. Male of 
T. aequatorialis. 1 c. Spermatozoa of male. 1 d. Winter egg. 
Floscularia torquilobata. — Fig. 2. Ventral view. 
Brachionus furculatus.— Fig 3 a. Dorsal view of female. 3 6. Ventral view of lorica of 
female. 3 c. Side view of female. 3 d. Dorsal view of male. 3 e. Ventral view 
of male. 3 /. Diagrammatic section of male. 
Bhinops orbiculodiscus. — Fig. 4 a. Ventral view. 4 6. Side view. 
Notommata cuneata . — Fig. 5 a. Dorsal view. 5 6. Dorso-lateral view. 
Salpina cortina. — Fig. 6. 
Anuraea procurva. — Fig. 7 a. Dorsal view. 7 6. Side view. 
Anuraea scutata. — Fig. 8 a. Dorsal view. 8 6. Side view. 8 c. Anterior mental edge of 
lorica. 
1891. 
Y 
