108 THE VOYAGE OF H.M.S. CHALLENGER. 
Calicles closely placed, separated by spaces equal to about half of their diameter or less 
except at the outer part of the colony where they are more distant; circular, deep, 
slightly prominent, rather large, being from about 2°5 to 3mm. wide; costee distinct only in 
the neighbourhood of the calicles, the outer border almost vertical, thickened and denticu- 
late ; the intercalicinal spaces finely and irregularly echinulate ; walls thin ; septa of three 
complete cycles, slightly thickened at the wall; the first and second cycles equal, exsert 
and subtruncated, finely denticulate, very granulated, broad, leaving a very narrow central 
space, at the bottom of which is the well-developed and trabeculate columella, chiefly 
formed by the perforated edges of the septa; septa of the third cycle, generally narrow 
and thin, and distinct only at the wall. Exotheca subvesicular, rather dense and 
compact. 
This species is named after the late Dr. Briiggemann, who first recognised its 
specific distinctness, but did not describe it. Owing to the equal prominence of the 
primary and secondary septa, the calicles have a very even and regular appearance. 
One specimen in the collection presents an interesting variety of growth, which seems 
to have been produced by injury due to exposure. Apparently the polyps over nearly 
the whole surface must have been killed, except on a small area, from which subsequent 
growth has proceeded, covering a considerable lateral portion of the old corallum with a 
thin layer, the edges of which are clearly distinguishable from the older growth. 
Locality.—Mactan Island, Philippines. 
Genus 26. Leptastrea, Milne-Edwards and Haime. 
Leptastrea et Baryastrea, Milne-Edwards and Haime, Cor., ii. pp. 493, 512. 
Following Klunzinger,’ I have united the Leptastrea and Baryastrea of Milne- 
Edwards and Haime under the former name. These genera do not seem to be separated 
from each other by any character of classificatory value. 
Four species are in the collection, obtained at Tahiti. Three of them do not seem to 
differ in any marked character from the Red Sea forms. 
1. Leptastrea solida (Milne-Edwards and Haime). 
Baryastrxa solida, Milne-Edwards and Haime, Cor., ii. p. 512, pl. D. 8, fig. 2. 
The larger calicles in this species often attain a diameter of 5 mm., with the fourth 
cycle imperfectly developed. 
A small specimen occurs in the collection. 
Locality.—Tahiti. 
1 Cor. roth. Meer., iii. p. 43. 
