THE STONY CORALS OF THE PORTO RICAN WATERS. 
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Quelch’s and Gregory’s original specimens, in the British Museum (Natural History) ; and the excellent 
collection of the United States National Museum, which possesses Dana’s type of Meandrina strigosa. 
The first available name for this species is viridis of Le Sueur. The name labyrinthica of Ellis & 
Solander can not be used, as Pallas had applied it to Madrepora mxandrites Linnaeus. The sinuosa of 
Le Sueur is a misidentification of the Madrepora sinuosa of Ellis & Solander, so it can not be used. 
The next name is var. viridis of Le Sueur. The varietal name is here raised to specific rank. 
There are over 20 specimens of the Platygyra viridis group in the U. S. National Museum. Before 
proceeding to a discussion of the specimens it would be best to examine Milne-Edwards & Haime’s 
mode of classification of the species of the genus, and those of their species that come from the West 
Indies. 
Their first section comprises. forms with “Le polypier formant une masse fortement gibbeuse ou 
meme lobee,” which comprises M. jilograna (Esper) and M. grandilobata M.-E. & H. (to which should 
be added M. clivosa of Ellis & Solander, sp. ). The second division has “Le polypier formant une 
masse legerement gibbeuse” (here is placed M. superficial is) ; the third “Le polypier formant une masse 
simplement convexe sans gibbosites,” and contains M. heterogyra, M. sinuosissirna, M. serrata, and M. 
crassa. Mseandrina valida and M. mamr.iosa Dana are placed in the “ especea douteuses,” and Meandrina 
strigosa Dana is referred to Cceloria as a doubtful species. 
To tabulate the characters which separate heterogyra, sinuosissirna, serrata, and crassa: 
31. heterogyra Corallum convex, oblong; 12 to 14 septa to cm., usually equal; width of valleys, 6 mm.; 
depth, 4 or 5. 
31. sinuosissirna The points of difference given by Milne-Edwards & Haime are the subspheroidal form, 
the septa crowded and alternating in size, narrow above and enlarging in the 
interior of the valleys. Valleys nearly a centimeter wide. 
31. serrata Would be separated from preceding by having valleys 7 mm. wide and 5 mm. deep. 
31. crassa Form as in heterogyra , otherwise resembling sinuosissirna, except that the columella is 
greatly developed and valleys are 7 mm. wide and 3 or 4 mm. deep. 
Milne-Edwards & Haime have based their division of these forms into 4 species on the following 
characters: (1) The corallum being elongate or subspheroidal; (2) the septa being all of the same size 
or alternately larger and smaller; (3) the collines being rounded above or acute; (4) the width of the 
valleys ranging between 6 mm. and 1 cm. in width and 3 to 5 mm. in depth. Minor importance is 
laid on the septal dentations and the development of the columella. I came to the conclusion that we 
have to deal with a single species from an examination of the Duchassaing-Michelotti material in 
Turin, and again to the same conclusion from a study of the specimens of Milne-Edwards & Haime in 
Paris and the specimens in the British Museum. I shall now describe in detail a single specimen 
from Belize, Honduras (collected by A. E. Morlan). 
The specimen is about 23.5 cm. long by 19 cm. wide on the flattish base, and approximately 10 
cm. high; i. e., the form is oblong. On one end the valleys are extremely sinuous, while on the 
other they are usually parallel, running perpendicular to the axis of elongation of the colony, and 
show very few sinuosities. The width of the valleys varies from 4.5 mm. to 9 mm.; i. e., in width of 
valleys this specimen takes in all species. The depth of the valleys varies from 2 mm. to 6 mm. ; this 
specimen shows depths of valleys both lesser and greater than the extremes recorded by Milne- 
Edwards & Haime in their characterization of the species. The walls between the valleys are solid, but 
may vary somewhat in thickness. The septa probably present the greatest variation of any element of 
the corallum. For long distances there may be only large septa, with no hint of smaller septa between 
them, whereas on other portions of the surface the alternation of larger and smaller is perfectly 
regular. A place where there are only larger septa shows twelve to the centimeter on one side of the 
colline and thirteen on the other. In another place, where there is fairly regular alternation of larger 
and smaller, there are fourteen larger and thirteen smaller to the centimeter. These measurements 
cover all the four so-called species. The septa may be narrow at the top, sloping downward into the 
bottom of the valley, thus giving the colline a triangular profile, or they may arch gently over the top 
of the colline and have their inner margins fall perpendicularly to the top of the paliform lobe at the 
base. The paliform lobes may -be entirely suppressed or they may be greatly developed, but whenever 
the inner margins of the septa fall perpendicularly to the bottom of the valley the paliform lobes are 
well developed. The septal dentations are usually quite regular, and are like the teeth of a saw ( “en 
scie”), but there may occasionally be slight irregularities. The columella varies much. It may 
consist of weak, spongy calicinal centers, each pair connected by a septum, representative of a lamellar 
