218 Proceedings of the Royal Physical Society. 
twenty times as long as the animal, and clothed at its upper 
part by about forty scattered tentacles, which twine about 
in most violent motion. The animal seems to be constantly 
searching the water around for prey, and occasionally to 
press the tentacles firmly against the body of the proboscis, 
as if to imbed some matter into the soft substance of the 
latter — the usual mode of feeding amongst the Acinetiens, to 
which class it belongs. It is impossible not to be struck 
by the extreme similarity in outward form between this 
animal and the Echinoderm Sipunculus Bernhardi. In both 
animals occur the same shapeless body, the same entirely 
retractile proboscis crowned with tentacles, and the same 
peculiar motions in seeking for prey. But with the form, 
the similarity ends, for the Echinoderm possesses a highly 
organised structure, while in the transparent Protozoon no 
structure at all has been detected. 
(2.) On Hermajphrodite Reproduction in Chrysaora hyos- 
cella. (Plate IX). — Professor Allen Thomson, in his " Trea- 
tise on the Ovum,"* states that " the Discophoros (Medusae) 
are of distinct sexes." I have found this to be the case in 
all the Steganophthalmata and Gymnophthalmata which I 
have examined, with the exception of the subject of this 
notice. 
Large individuals of (7. hyoscella are hermaphrodite ; but 
smaller ones are found which are unisexual, the male or 
female element being suppressed, as in some dioecious plants. 
The best method of examining the structure of the repro- 
ductive apparatus of this animal is to place the Medusa, in 
its natural position, in a large basin of sea-water. The um- 
brella, all but its margin, is then to be cut away. The cavity 
of the stomach is thus laid open, and we have a good view 
of the interior aspect of the sub-umbrella. We find that 
each lip of the mouth divides, at its insertion, into three 
pillars. The central pillar projects as a large rounded bulb 
into the stomach, while the lateral ones diverge, pass out- 
wards towards the margin, and afterwards converge and 
unite together, so as to form, with the bulb of the central 
pillar, the thickened opening or framework of the ovarian 
Cyclopaedia of Anatomy and Physiology, vol. v. p. 129, " Acalephse." 
