153 
At Station 204: B. compressus n. sp., and B. proripiens n. sp. At this Station two 
species of Scalpellum also were collected (See p. 56 of this report). 
At Station 260: B. albus n. sp. B. auricoma n. sp., and B. tnvestitus n. sp. 
At Station 310: B. zmvestetus n. sp.. B. maculatus n. sp., and B. maldivensis. 
All the species of Aadanus were found in the neighbourhood of the coast. Several of 
them were caught in shallow water, some in rather deeper water, and only a few in water 
of greater depth than 100 m. The greatest depth found inhabited by a species of this genus 
was 564 m.; at depths of more than 600 m., at which 26 species of Sca/pel/um were collected, 
not a single species of Ba/anus was observed. 
Several species seem to spread over a rather considerable range of depth: as for 
example 2B. maldivensts, which was observed at depths of 54—91 m., 70 m., 216 m., and 
even of 390 m., and 4. aléus at depths of 90 m., 289 m., and, probably, even at a depth of 
522 m. The following table contains the species of Balanus collected during the cruise of the 
Siboga, arranged according to the depth at which they occurred: 
B. tintinnabulum Linn. B. hystyi# n. sp. . . . 40m. (or less) 
(in different varieties). . . . Surface. B. navicula Darwin. . 45 m. 
B. amphitrite Darwin ... . Surface—56 m. | B. terebratus Darwin . 52 m. 
ieancaarus th. SP? . . 2 2. . 9 —36m. B. maldivensis Borradaile 5 4—390 m. 
ee socuiles Tloek 2. . . . + « 9—=—36m: B. maculatus n. sp. . . 7O—73 Mm. 
POUR My SPs ss 30 2.2 -. 13——31 m: B. investitus n. sp. . . 73—90m. 
B. amaryllis Darwin... . . 13—40m. B. proripiens n. sp. . 75—94m. 
B: auricoma n. spec... ... 27(and?90m.),| B. compressus n. sp. . 75—112 m. 
Bensaueoruws Ellis . 9: . . .. - 32m. | Buwminuins a: sp... = som: 
ECOLIMUUS SPs ie. + 4: «32 i. B. albus n. sp. . . . . 9o—28g9 (and? 522 m.) 
~B. quadrivittatus Darwin. . . 32m. B. pentacrini n. sp. . 204—304m. 
B. quinguevittatus n. sp... . 32m. PS TEMUISEROCKS “we 275 TM 
GB. ciliatus N..sp...... . + 34—113 mM. BE HHUSINE SD Nas) SOA: 
B. longirostrum n. sp... . . 36m. ) 
A few remarks may be added with regard to the geographical distribution of these species 
of Lalanus. That 16 species were collected, which were not observed before, does not prove, 
of course, that they do not occur outside the Malay Archipelago : the exploration of this region 
on this occasion has been a very careful one; therefore, it cannot be considered improbable, 
that at least some of these species will be found in other regions of Eastern Asia, should 
they be explored with the same care and thoroughness, as the Malay Archipelago has been. 
Of the species collected by H. M.S. “Siboga”, which were already known, 2. amphitrite and 
B. tintinnabulum seem to have the widest distribution, which no doubt is due partly to their 
being often found on ships-bottoms: they are sometimes associated with one another even on the 
same ship. B. calceolus, B. navicula, B. amaryllis, and B. maldivensis are known to occur in 
British India also, and B.amaryélis in Australia as well. B. guadrivittatus, B. soctalis, and B. 
25 
SIBOGA-EXPEDITIE XXXI4. 20 
