REPORT ON THE CIRRIPEDIA. 
41 
the centre of the egg, ancl in the second place, rounded groups of very small ovigerms, 
forming together what the Germans call the “ Ke im L ager.” One or two of these ovi- 
germs are often slightly larger than the rest, and these will be the first to develop into 
ovarian eggs after those which are already mature are evacuated. 
In a ripe or nearly ripe ovarian egg of Scalpellum vulgare which had a diameter of 
0'3 mm., a nucleus of 0’036 mm was present, having a nucleolus of (P009 mm. The 
nuclei of the cells placed along the wall of the ovary are oval and measure about 
0‘01 by 0'005 mm.; the small ovigerms are nearly circular and have a diameter of 
about 0‘013 mm. Their nuclei, of course, are a great deal smaller than those of the ripe 
ovarian eggs. One of the ovigerms was considerably larger ; it was rounded oval, its 
diameters being 0'03 and 0’023 mm.; its nucleus was about O'0 12 mm. A ripe ovarian egg 
of Scalpellum vulgare is filled with a coarsely granulated vitelline mass (PI. VI. figs. lA, 
2x). Between the larger granules, which in the microscopical preparations appear like 
vesicles, a much more delicately granulated mass of plasma is here and there visible ; 
sometimes a layer of this is placed in the centre round the nucleus. The wall of 
the ovarian egg seems to be a very thin and structureless membrane, and neither 
in the case of Scalpellum, nor of any of the other genera observed, was a follicular 
epithelium present. The mature ovarian eggs of Scalpellum regium are about 
0‘6 mm. in diameter. They are very coarsely granulated; they do not quite fill 
the interior of the ovarian cceca, but between them, and also between each egg and 
the wall of the coecum, a layer of a much more delicately granulated mass of plasma is 
visible (PI. VI. fig. 3). Here the ovigerms form groups of little cells, the dimen- 
sions of which nearly correspond to those of Scalpellum vulgare. In one of these groups 
I counted about 20 of these ovigerms. Here again one of these ovigerms was developed 
into a young ovarian egg. The wall of the coeca shows the same cellular elements as in 
Scalpellum vulgare ; its outer surface is formed by a distinct membrana propria, which 
may be composed of stronger fibres of connective tissue, but which often looked as if 
composed of circular muscular fibres. The wall of the oviducts, however, did not show 
the same stronger outer wall ; it is composed of a distinct epithelium and a very narrow 
or thin membrana propria. 
Whereas in Scalpellum vulgare each oviduct gives off a coecum only once, and this 
coecum, which starts from the oviduct at the superior extremity of the peduncle, divides 
again and again, the oviduct in Scalpellum regium penetrates into the interior of the 
peduncle for about one-third of its whole length. In different places each oviduct in this 
species gives off coeca, and these form together so voluminous a mass that the peduncle is 
filled with it up to its inferior extremity. 
The oviduct of Scalpellum vulgare appears in a transverse section as an exceedingly 
narrow slit, and 0'2 mm. in length. The oviduct of Scalpellum regium (PI. V. 
figs. 8 and 9), in a transverse section shows an irregularly folded wall ; its largest 
(zool. CHALL. EXP. — PART XXVIII.- — 1884.) Ee 6 
