THE STONY CORALS OF THE PORTO RICAN WATERS- 
317 
Porites astreoides Lamarck. Pis. xxxn, xxxm, xxxiv. 
1816. Porites astreoides, Lamarck, Hist. Nat. Anim. s. Vert., t. ir, p. 269. 
1829. ? Porites conglomeratus, Eiehwald, Zool. Spec., p. 183. 
1861. Porites incerta, Duchassaing & Michelotti, Mem. Corall. Ant., p. 83 (of reprint). 
1861. Porites guadalupensis, Duchassaing & Michelotti, op. sup. cit., p. 83. 
1861. Porites agaricus, Duchassaing & Michelotti, op. sup. cit., p. 83. 
1863. Porites collegniana, Duncan, Quart. Jour. Geol. Soc. London, vol. xix, p. 437 (non Michelin, 1842). 
1866. Neoporites littoralis, Duchassaing & Michelotti, Sup. Mem. Corail. Ant., p. 97 (of reprint). 
1866. Porites michelini, Duchassaing & Michelotti, op. sup. cit., p. 98, pi. x, figs. 9, 10. 
1866. ? Porites subtilis, Duchassaing & Michelotti, op. sup. cit., p. 98, pi. x, figs. 7, 8. 
1866. Porites superficialis, Duchassaing & Michelotti, op. sup. cit., p. 99. 
1866. Cosmopolites Ixvigata, Duchassaing & Michelotti, op. sup. cit., p. 99, pi. x, figs. 12, 16. 
1868. Porites soHdo, Verrill, Trans. Conn. Acad. Sci.,vol. I, p. 358. 
1880. Porites astrxoides, PourtalOs, Mem. Mus. Comp. Zool., vol. vn, No. i, pi. xvi, figs. 1-12. 
1892. Porites verrilli, Rehberg, Abhandl. Naturwiss. Ver. Hamburg, Bd. xn, p. 48. 
Ehrenberg’s Madrepora ( Pontes ) astrieoides is not a Porites but is a Stylophora, >St. ehrenbergi 
Milne- Ed wards & Haiine. 1 
The only point in the synonymy of this species demanding especial consideration is the treat- 
ment accorded the species of Duchassaing & Michelotti. I found in Turin the types of five of the 
eight species described by these authors, viz. littoralis, superficialis, guadalupensis, incerta, and agaricus. 
I could not discover differences of sufficient importance to establish even varieties. There remain 
Neoporites michelini, N. subtilis, and Cosmoporites Ixvigata, all of which are figured; besides, the names 
are accompanied by poor, brief Latin descriptions. Neither the descriptions nor figures show any 
characters of value, unless it be in the figure of the calice of subtilis showing a greater number of septa 
than in the other species. 
Pourtales has published superb figures in Agassiz’s Florida Reef Corals (Mem. Mus. Comp. Zool., 
vol. vii, No. 1, 1880). 
Two species grouping with astreoides remain to be considered, viz, Porites solida Yerrill (non 
solida Forskal)=P. verrilli Rehberg, 2 and Porites branneri Rathbun. The former, P. verrilli Rehberg, 
must in my opinion be placed in the synonymy of P. astreoides. There are several excellent speci- 
mens in the United States National Museum from Rio Formosa, Pernambuco, Brazil (collected by the 
Hartt Expedition, 1875) . These specimens have the same general appearance as astreoides. The only 
feature that could be used for specific differentiation is the usually constant presence of a solid 
columella, which may have a small slight styliform projection in the center. There are twelve septa, 
no pali, and the wall is as in astreoides. The difficulty about using the difference of the columella as of 
specific value is that in the specimens of verrilli it shows variation in the degree of compactness, 
while in astreoides we can find in the same specimen the typical verrilli condition or a weak style with 
very little or no basal deposit around it. There can be no varietal difference. 
Porites branneri Rathbun seems to be a distinct species. There are in the United States National 
Museum several specimens from Pernambuco, Brazil (Hartt Exp., collector). The species grows in 
small, incrusting masses. The calices are smaller than is common in astreoides, but the distinguishing- 
feature is the constant presence of five pali; they are rather slender and erect. The columella space 
is usually vacant, sometimes a “columellar tangle” is present. The species needs further study, for it 
suggests the young colony of Porites porites (Pallas). 
In P. astreoides the usual number of septa is twelve, but sometimes rudimentary septa are present 
between the larger. 
There are six excellent specimens of this species, which may be divided into two formic. 
Forma a , PI. xxxii and PJ. xxxiv, fig. 1. — To this form four of the specimens belong. It is 
especially characterized by the surface of the corallum possessing numerous gibbosities. Certain 
features of the specimens belonging to this form may with propriety be described in some detail. The 
edge of the wall between the oorallites is acute; the calices are rather deep. The diameter ol the 
calices is 1.5 to 2 mm. There are usually twelve large septa with rudimentary or smaller septa quite 
1 Hist. Nat. Cor., t. II, p. 139. 
2 Neue und wenig bekannte Korallen, Abhandl. Naturwiss. Ver. Hamburg, Bd. in, pt. 1892, r. p. 48. 
