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BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Next in the series come two Challenger specimens from St. Thomas, which show the characters of 
M. prolifira so unmistakably that they were referred to that species by Quelch. In one of these the 
branches form a complanate but not solid frond; usually from 2 to 5 branchlets are collected together 
in flattened groups and fused together laterally; they vary from 7 to 12 mm. in thickness, including 
wall. Radial" corallites spreading at an angle of about 45°, tubular, with an oblique aperture, or 
nariform, rather unequal, 1 to 3.5 mm. long, with immersed ones between, especially in the line of 
fusion. The other specimen has stouter and less confluent branches, with radial corallites which, in 
some parts, recall the condition characteristic of M. cervicornis.” 
I went over carefully, in the British Museum, all of the specimens upon which Brook based his 
notes, and it seemed to me that his conclusion was correct. I have had photographic illustrations 
made of a number of specimens, and give here a resum6 of the features exhibited by them. 
PI. xxn, fig. 2, is the end of a branch, 20.5 cm. long, of the cervicornis variety, showing several 
branchlets. PI. xxi represents a specimen, 37.5 cm. high, of the same forma. PI. xxii, fig. 1, is the 
end of a branch of the prolifera variety, showing some branchlets slightly fused one to another, 
PI. xxiv represents another specimen of prolifera , 39.5 cm. high, in which the branches and branchlets 
are somewhat crowded but remain separate. Specimen, pi. xxiii, also ol prolifera, 35.5 cm. high, has 
the branches crowded and frequently fused one to another in the same plane. PI. xxv represents still 
another specimen of prolifera, 51.3 cm. high, in which there is still greater fusion. As the illustra- 
tion is only about one-half natural size, it does not show the fusion so forcibly as the specimen itself. 
PI. xxvi represents a small specimen of palmata, greatest length 23.2 cm., which shows the courses 
of the small branches and the free ends of branches around the margin. PI. xxvii represents a young 
specimen of palmata, breadth 14.8 cm. Even in this specimen faint indications of component, fused 
branches may be seen. 
These plates, together with the quotation from Brook, will show how the transformation in 
form takes place. Forma cervicornis ( muricata s. s.) stands at one extreme, and forma palmata stands 
at the other. The plates published by Pourtales 1 form an interesting series for comparison in this 
connection. 2 
Family P0RITID7E Dana. 
Genus PORITES Link, 1807. 
Porites porites (Pallas). 
1756. Corallium, poris stellatis, etc., Seba, Thes., t. in, p. 202, pl.cix, fig. 11. 
1766. Madrepora porites, Pallas (pars), Elench. Zooplr., p.324. 
1895. Porites clavaria, Gregory, Quart. Jour. Geol. Soc. London, vol.Li, p.282, with synonymy. 
The reasons for the use of the specific name porites probably should be stated. The Madrepora 
porites of Pallas was not applied to what is now considered a species by any one, but would apply to 
any Porites. If his specific name is to be retained it must be restricted to some one species included in 
the original group of species. Milne-Ed wards & Haime 3 place “ Madrepora porites (pars) Pallas” in the 
synonymy of Porites clavaria Lamarck, and also place “Corallium poris stellatis, Seba, Thes. loc. rer. 
nat., t. in, p. 202, tab. cix, No. 11” in the synonymy of the same species. Pallas in his synonymy of 
1 Mem. Mus. Comp. Zool., vol. vn, No. 1, pis. xvii-xix. 
2 Since this manuscript was prepared Prof. J. W. Gregory has published a paper entitled “ On the W est-Indian Species 
of Madrepora” (Ann. and Mag. Nat. Hist., 7th ser., vol. Vi, No. 31, July 1900, pp. 20-31), in which he concludes that the three 
traditional species of Madrepora should be recognized, considering that he was mistaken in the opinion expressed in his 
“Contributions to the Palaeontology and Physical Geography of the West Indies.” From the evidence presented in my 
own discussion of the subject, I have arrived at the same conclusion as Brook, i. e., it seems to me that the three do inter- 
grade. However, I believe in the retention of the three usually recognized forms of the species. Whether these three 
forms should be called species, forms, varieties, or subspecies depends upon the individual definitions of these words. In 
my opinion the proper treatment is to consider all of these forms as one species, because of intergradation, and that as the 
forms are usually distinct they should be differentiated and designated by names of value subordinate to that of the name 
species. On the other hand, if the existence of not very numerous specimens indicating intergradation is not considered 
sufficient to overthrow a species, the three form's should be considered species. The question is very largely one of 
nomenclature. Such discussions as that of Gregory, the one given by Duerden in the Jour. Jamaica Institute, vol, ii, 
No. 6, 1899, pp. 621, 622, and the one given here by myself aid in understanding the biology of these forms, no matter 
by what nomenclature they are designated. Duerden could find no difference in the polyps of the three forms. 
I have recently seen, in possession of a curio vender at Palm Beach, Florida, a collection that bridges completely 
any imaginable gap between prolifera and palmata. 
3 Hist. Nat. Corail., t. in, I860, p. 175. 
