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grande Sowerb. Jr., but the exact place where they were collected is not given; the second 
is represented by two specimens and is a new species for which I propose the name P. kurz 
after the island in the neighbourhood of which, at a depth of 200 m., it was collected: so 
far as I know this is the first instance of a species of this genus being found at such a 
great depth. The third species of the Siboga collection is also new to science. I wish to 
introduce it into the system under the name of P. jedanz, again after the island where it was 
collected. Both new species are very characteristic, and will be easily distinguished from Darwin's 
species, should they again be found. 
The number of species occurring in the Malay Archipelago has now increased to seven; 
some of them at least seem to have only a local distribution, and perhaps other species may 
still be found should more remote parts of the Archipelago be carefully explored. 
About the bathymetrical range of the species of this genus, we are not well informed 
at present. Most specimens were collected during coast-exploration, most species seem only to 
occur in shallow water. Probably this is also the case with two of the species represented in 
the Siboga-collection: viz. P. grande Sowerb. Jr., and P. jedant n. sp. The third (P. kurz 
n. sp.) was dredged at a depth of 204 m., which certainly shows that their occurring in 
shallow water is a rule not without an exception. 
1. Pyrgoma grande (Sowerby. Jr.). 
DARWIN, CH., Monograph. The Balanidae, Verrucidae etc. 1854. p. 365, pl. XIII, fig. 1a—td. 
About half-a-dozen specimens of this species were collected during the cruise of 
H. M. S. “Siboga”. Unfortunately the station where this species was collected has not 
been noted, the label bearing only a query— a very great exception in the case of this 
expedition. 
The appearance and structure of shell and basis much resemble the description as given 
by Darwry. Darwin, however, complained that the internal organs of most species of Pyrgoma 
are badly preserved, and, in consequence, has only been able to investigate the structure of 
the mouth and the cirri of P. anglicum, P. milleporae and P. crenatum. Just to compare 
the structure of these parts in P. grande with those of my new species P. kurz, I dissected 
one of the specimens; and as the structure of the said organs was foand to be of some 
interest, I will insert here the following description : 
Mouth. Labrum deeply and widely notched; a large number of small triangular and 
pointed teeth arranged in several rows on both sides at the entrance of the notch. Palpi 
stout, broad, short, with the tip rounded and with numerous shorter hairs disposed along the 
inner surface, longer ones at the tip, and very long but not very numerous ones near the 
extremity of the upper margin. 
Mandible with four teeth, and the inferior angle not produced; the latter has a series of 
small triangular, partly blunt and partly pointed teeth along the anterior margin; in the man- 
dible of the left side, one of these teeth is developed somewhat more strongly and might be 
considered as a fifth mandibular tooth. The first tooth is single, relatively short and pointed, 
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