ON AMPHIPORUS SPECTABILIS, 291 
probable. The water at any rate—judging from analogy 
—must be loaded with ripe spermatozoa in vast multitudes. 
In a very fine Amphiporus hastatus from Southport sands 
(in October) I was struck by observing in longitudinal 
sections a somewhat regular arrangement of cut cellular 
tubes. This appearance is due to aseries of tubes filled with 
granular nucleated cells (Plate XIV, Fig. 3, 9,9), which pass 
downwards at tolerably regular intervals from each side of 
the proboscidian sheath, and terminate at a fissure of the 
longitudinal muscular coat a little above the nerve-trunk. 
Similar tubes curve along the ventral surface beneath the 
alimentary chamber, and terminate at the same points (g’). 
The enormous number of these cells show that if they are 
ova the majority become absorbed as development proceeds ; 
but of course this is conjecture. Investigations on the living 
animals will show the importance of these organs in the 
physiology of reproduction. As indicated formerly, a similar 
tendency was observed in the posterior part of Dr. Hubrecht’s 
specimen, which anteriorly was distended with spermatozoa. 
The Pelagonemertes Rollestoni of Mr. Moseley,! of the 
“* Challenger ”’ expedition, occurred near the southern verge of 
the South Australian current, and in all probability will be 
found to be one of the Enopia, if the author is accurate in 
affirming that the mouth opens in front of the ganglia, and 
the external muscular fibres of the body-wall are circular 
and the internal longitudinal. ‘The digestive canal is gene- 
rally more or less pinnate in the ENopia,and characteristically 
so, for example, in Nemertes gracilis. 
The elaborate paper on the histology of the land Plana- 
rians of Ceylon in the ‘ Philosophical Transactions’ for 1874, 
by the same author,” forms an important contribution to our 
knowledge of the ‘subject, and as Bipalium was examined 
when treating of the homologies of the Nemerteans, a com- 
parison of the observations may be useful. 
In regard to the hypoderm or cutis (his epiderm), Mr. 
Moseley observes that it alters its character on each side of 
the ambulacral line, and “‘ becomes far thicker and apparently 
less definite in structure.’ In my specimens (for which I 
have to thank Dr. Percival Wright), the mass of the cutis 
(or hypoderm) was much thicker and denser on the dorsum, 
more translucent on the ventral median ridge, and the layer, 
as indicated by the basis-structure, decidedly narrower. ‘The 
region above is certainly greatly hypertrophied. The hypoderm 
1 «Ann, Nat. Hist.,’? March, 1875, p. 1, Plate XV, B. 
2 [ have to acknowledge the courtesy, of Prof. Rolleston in kindly pro- 
curing me a copy. of this paper during the absence of the talented author in 
the “ Challenger.” 
