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J/, striatum which was taken by the "Challenger" in the Philippine Archipelago at 

 depths of I So and 207 m. was collected by H. M.S. "Siboga" at different places in the Malay 

 Archipelago at depths from 204 to 984 m. M. carino-dentatuni was found on the stem of a 

 Hyalotiema from the Gulf of Bengal, dredged at 3200 m. AI. lineatum was dredged in the 

 Malay Archipelago from a depth of 450 m. So all the species may be considered as deep-sea 

 forms, the range of depth over which they spread being very large. Hitherto, the genus has 

 only been found in Asiatic Indian Waters. 



1. Megalasma striatum Hoek. 



1883. Hoek, Cirripedia of the "Challenger", p. 51, pi. II, fig. 5—9, pi. VII, fig. 8 — 9. 



The "Challenger" collected this beautiful species in the Philippine Archipelago at a 

 depth of 100 a 115 fathoms, about 180 a 207 meters, in November 1874. 



It has not been observed, so far as I know, from that date until H. M. S. "Siboo-a" 

 dredged some specimens in 1899 at different stations, viz. 



Stat. 251. December 8, 1899. Lat. 5°28'.4S., Long. 132° o'. 2 E. Depth 204 m. Bottom: hard 



coral sand. Numerous specimens attached to the spines of an Echinus. The largest 



specimen measures 10,5 mm. 

 Stat. 253. December 10, 1899. Lat. 5°48'.2 S., Long. 132° 13' E. Depth 304 m. Bottom: grey 



clay, hard and crumbly. One small specimen attached to the spine of an Echinus. 

 Stat. 267. December 20, 1899. Lat. 5° 54' S., Long. 132° 56'./ E. Depth 984 m. Bottom: grey 



mud with a brown upper layer. One specimen attached to the silicious skeleton 



of a sponge. 



The range of depth of this species is now found to be much greater than could be 

 judged from the results of the Challenger: we are now permitted to say that this species is 

 one of those capable of existing at a considerable variety of depth. 



At the same Stations where this species was collected, other Cirripedia were also brought 

 up with the dredge; thus, at Station 251 : two species of Poecilasina^ four species of Scalpellum, 

 one of Balamis etc.; at Station 253: three species of Poecilasina etc. The conditions must be 

 particularly favourable for the development of Cirripedia at these Stations! With reference to 

 this, see my Report on the Cirripedia of the "Challenger", p. 25. 



2. Alcgalasma lineatum n. sp. PI. IV, fig. i — 8. 



Scutum with the carinal margin bowed, considerably longer than the straight tergal margin 

 and with a distinct though short basal margin. Tergum triangular, small. Carina with the lower 

 end truncate and very wide, the upper end narrow and elongated. Peduncle extremely short. 



General appearance. PI. IV, fig. i and 2. Capitulum elongated, about twice as long 

 as broad, swollen in the middle. The short peduncle extends from underneath the capitulum. 

 The short basal margin of the scutum forms the continuation of the truncate basal margin of 

 the carina. The valves are delicately striated; strips of membrane run over the lines separating 

 the valves. 



Scutum (fig. I and 3^) elongated, not exactly triangular, there being a short basal 



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