Descrij^tioii of New Protozoa. 
27 
viridis, which I had discovered some time before, together with 
two other species, Lagotia hyalina and atro-purpurea' 
The present species, Lagotia productay was found in great 
profusion in the tanks of Miss Gloag of Queensferry, in August 
last, and resembles Lagotia viridis in its general characters. 
It has the same long green body, surmounted by a horse-shoe- 
shaped or two-pronged rotatory organ, each prong formed of 
a membrane folded together, like the ear of a hare, and edged 
by a muscular band fringed with vibratile cilia. It inhabits 
also a similar flask-shaped cell, with bent neck and trumpet- 
shaped mouth. But the body of Lagotia producta is greatly 
prolonged in comparison with that of Lagotia viridis; the 
colour nearly black, and the gullet a wide sac, and not a 
spiral canal. In the present species, the neck of the cell has 
become a long wide tube, greatly disproportionate to the flask- 
shaped part from which it projects ; the whole bearing some 
resemblance to a long jack-boot. A careful examination of 
the anatomy of the cell reveals a structure of singular interest 
and beauty. It consists of three elements— (1.) a horny or 
chitinous case, lined with (2.) a layer of dark green sarcode, 
and covered with (3.) a thin layer of colourless sarcode ; so 
that the cell is not a mere extraneous house in which the ani- 
mal lives, but is a quasi-bony framework, buried in an exten- 
sion of the living flesh of the animal, and growing with its 
growth. And this, I believe, holds good with regard to the 
tubes of other genera of Vorticellina. It is especially to 
be seen in Vagincola valvata, a species which I have de- 
scribed to the Society, and in which the layer of sarcode lining 
the tube serves to support and partly to form a valve, which 
rises and falls with the movements of the animal within. 
The chitinous case of L. producta^ or that part of it cor- 
responding to the body of the flask, resembles that of Lagotia 
viridis ; but the neck or tube is composed of a spirally-wound 
ribbon of chitine, the upper edge of each spiral slightly over- 
lapping the lower edge of the spiral arising above and within 
it, and being slightly everted. The edges have no chitinous 
connection with each other, but are retained in their places 
by their fleshy coverings. One might suppose that the tube 
was formed and gradually increased in length by a continual 
