314 Mr. J. Alder on some New and Rare Zoophytes 
Corymorpha nana. Pl. XV. figs. 1-5. : 
Corymorpha nana, Alder in Tynes. Club Trans. vol. iii. p. 108, 
It is now nearly twenty years since I first met with this. 
interesting little species, at Newbiggin, from which time I had 
looked for it often without success until the summer of 1860, 
when I fortunately obtained two living imdividuals at Culler- 
coats. This puts me in a position to add considerably to the 
information hitherto published concerning the species, as well as 
to give more correct drawings of it in the living state. Cory- 
morpha nana is a very active animal, constantly changing its 
form and the proportions of its parts. Sometimes the head is 
elongated into a slender tube, sometimes contracted so as to be- 
come nearly globular. The tentacles and body are equally sub- 
ject to dilatation and contraction in their different parts. In 
many of its states it bears a considerable resemblance to a minia- 
ture Corymorpha nutans, from which, however, it differs not only 
in its diminutive size, but in the smaller number of tentacles, 
and in the gonophores being sessile (not pedunculated or 
branched as in the latter), and large in proportion to the size of 
the animal. The medusoid differs from that of C. nutans in 
having the umbrella rounded at the top; in other respects it is 
very similar. The following detailed description will show the 
characters of this species more distinctly :-— 
Head subtubular, yellowish, the mouth conical, surrounded 
by about sixteen or eighteen short tentacles, forming two im- 
perfect rows. A single circle of fifteen to twenty long filiform 
tentacles surrounds the base of the head, immediately above 
which the gonophores form another circle of urn- or bell-shaped 
bodies, in different stages of development ; these are sessile, and 
in their more advanced state assume the perfect medusoid form, 
showing lively motions of systole and diastole for some time 
before becoming free. The body of the polype is elongated, 
tubular, and tapering to a point at the base ; it 1s soft and flexible, 
transparent, white or yellowish, with opake, white lines. It is 
enclosed in a transparent filmy sheath, ending at the base in a 
gelatinous mass (colletoderm of Wright ?) by which the animal 
is attached, though slightly, the pointed base of the fleshy body 
(ccenosarc) being free. Tubercles arise from the lower ends of 
thé opake white lines, which frequently enlarge into linear pro- 
cesses, whose use is not very apparent. They may possibly 
form additional organs of attachment, but in the specimens 
examined their ends were free. Length of the polype } to = inch. 
Medusoid with a rather deep, semiglobose, transparent, white 
umbrella, having four yellowish radiating canals; three of them 
ending in a yellow bulb at the margin of the umbrella, the 
