856 
THE VOYAGE OF H.M.S. CHALLENGER. 
“ Darwin’s ‘true ovaria,’ which Cuvier thought to be salivary glands, were also subjected 
to a close inspection, and were shown to be digestive glands pouring their secretions 
into the alimentary canal. The body of these glands is composed of one kind of cell 
only, belonging apparently rather to the pancreatic than to the hepatic cells, which are 
found in the digestive glands of the higher Crustaceans (Weber). To the same category 
of problematic organs, in which Cirripedia always were very rich, no doubt belongs 
the small organ of vision discovered by Leidy ; it is attached to the surface of the 
stomach and covered by the ligament between the two scuta, and by the muscles placed 
between this ligament and the widened stomach. Leidy ’s observation is quite in accord- 
ance with the facts, and these beautifully illustrate the persistence of an old larval 
structure which can hardly be considered to be of any use to the animal. 
“ Though in general Krohn and Kossmann had a correct notion of the structure 
of the’ female genital apparatus, our knowledge, as far as details are concerned, has 
been considerably augmented by the investigation of the Challenger material. The 
results of the researches with respect to this apparatus have been published in 
the last chapter of the Supplementary Report. The discovery of the occurrence 
of the segmental organ communicating with the exterior by means of the openings 
in the outer maxillae, perhaps casts light on the peculiar place of the female genital 
openings of Cirripedia. These would appear to be nothing but the openings of a second 
pair of segmental organs ; thus the first pair of segmental ■ organs furnishes a direct 
communication of the body-cavity with the surrounding medium, whereas the second 
serves for the evacuation of the female genital products.” 
The Pycnogonida . — “ The Pycnogonids form together a little group of Arthropodous 
animals. Though they are often met with by zoologists studying the marine fauna, 
they have hitherto, with a few exceptions only, been but superficially investigated. The 
naturalists who paid more special attention to the group had but few specimens at their 
disposal, and these belonged to a couple of species only ; thus it happened that though 
the number of papers treating of these animals had grown rather large, and though a 
considerable number of new species had from time to time been described, our know- 
ledge of the group was but little increased. By far the greater number of the species 
were described so inaccurately as not to admit of comparison with one another, and so 
far as the morphology of the group is concerned, we have till recently been almost 
entirely in the dark. The papers of Dolirn (1869) and Semper (1874) are among the 
first that tried to shed light on this question, and it is well known that they have 
arrived at very different conclusions. Dohrn’s conclusion was that the Pycnogonids, 
though not Crustaceans, appear by the presence of a Nauplius-lar.va in their ontogene- 
tical development to be nearly related to Crustaceans ; Semper, on the contrary, tried 
to demonstrate the truly Arachnid nature of these animals. 
