REPORT ON THE CIRRIPEDIA. 
7 
developed in the larvae of Lepas australis which I studied. Claus says that these glands 
consist of groups of cells which have either still the form of a sinuous string (“ eines 
gewundenen Stranges”), or which lie scattered by the side of one another; the latter is the 
case in Lepas australis. Claus has not observed the communication of these glands with 
the cement-duct which he figures ; at least in his figure they are at a very considerable 
distance from one another. I have not been more fortunate ; I even failed to observe 
the cement-duct. The different cells (PI. II. fig. 5) do not show much resemblance to 
the cement-glands of the full-grown animal ; yet I think that Claus’ supposition as to the 
nature of these elements is right. As regards the place they occupy in the Cypris-larva, 
it quite corresponds to the place they occupy in the full-grown animal, viz., in the 
most posterior (when the animal changes its position, the most superior) part of the 
peduncle. The Cypris-larva which furnished the drawing fig. 2 is a little older than 
the one figured in fig. 1. In the former the cement-cells are much more separated from 
one another than in the latter ; moreover, their nuclei are much more easily distinguish- 
able, and many of them are not so richly furnished with fatty granules as was the case in 
the younger condition. Very delicate and flat fibres in the later Cypris-stage are visible 
between the cement-cells ; probably they represent the canals figured by Claus and 
considered by him as branches of the cement-ducts. 
A pair of club-shaped bodies is situated near the ventral wall of the animal, the 
thickest part of which is directed towards the front of the Cypris and the narrower part of 
which can be traced as far as under the coeca of the oesophagus of this larva. These are 
described by Claus as the ovarium (figs. 1 and 2, Od ). I observed these bodies also, and 
I think it very probable that they represent the female genital apparatus ; they are 
especially distinct in the longitudinal section of the body shown in fig. 2. In this 
figure the valves of the Cypris are not represented ; the clear margin round the body 
represents the chitinous wall of the future Lepas ; the cells of the mantle serve as a 
matrix for its formation. 
When we look now at the figure of the Cypris-larva of Scalpellum regium which is 
destined to develop into a complemental male, we observe great analogy as well as 
considerable difference. PI. II. fig. 3 represents a larva which has probably attached 
itself lately, and which therefore is exactly in the same stage as the larva of Lepas 
australis which I have just described. It is somewhat different from the latter in 
general outline, being more elongate and not so high. At the hinder extremity the Cypris 
of Lepas australis is obliquely truncated and bluntly pointed, and that of the male of 
Scalpellum almost entirely transversely truncated. Like the former it is enclosed within 
a shell consisting of two valves of a very brittle constitution. The antennae (An) are 
stretched forward out of the ventral slit between the two valves ; they have in all essential 
respects the same structure as those of the full-grown complemental male, which will be 
described further on. At their base in the interior of the body of the larva a cellular 
