78 PROF. F. J. BKLL ON THE [Feb. 10, 



spines are not developed on all, though they are on most of the 

 ossicles ; and we frequently find, though without any definite regu- 

 larity, that two, or it may be three, spines are developed. When 

 this happens the spines are so set side by side as to lie across the 

 long axis of the arm ; they are not large, but their free end is 

 always bare of granules. The ossicles extend almost to the centre 

 of the disk. 



In addition to the lophial spines a number of others, almost if not 

 quite as large as they, are also developed ; a definite row runs down 

 either side of the lophial line, and in the wider portion of the disk 

 two other rows of spine-bearing ossicles are less distinctly developed. 

 The pore-areas are extensive, but not sharply distinguished from 

 one another, and the individual pores are large. The close granula- 

 tion of the superior ossicles and the intermediate pore-areas is hardly 

 less coarse than that of the lower surface. The madreporite is of 

 moderate size, irregularly elliptical, and about its own long diameter 

 from the centre of the disk. Notwithstanding the statement of 

 Miiller and Troschel, I venture to think that a perfect specimen 

 would present at any rate a few pedicellariae. 



Colour (when dry) : the distal parts of the arms light, the proxi- 

 mal brown, above ; the whole greyish brown below. The specimen 

 here under description is stated to have had the " tops of prickles 

 scarlet-red, upper surface tile-red." 



It was collected by Mr. Darwin at St. lago, Cape Verde Islands. 



Measurements: — R=9o; r=42 ; breadth of arm at base 41 

 millim. 



Oreaster reticulatus. 



Pentaceros reticulatus, Perrier, Rev. Stell. p. 246, where see the 

 complicated synonymy, and therein make the following corrections 

 and additions. — 



Insert "1766, Asterias)-eticulata, Linn. Syst. Nat. ed. x. p. 1099." 

 Jdd "page, p. 14," to "Retzius (1805)." 

 After "(1840) reticulatus," add " aeuleatiu, p. 2/7." 

 Add to reference to Grube in Archiv of 1857, — " Nova Acta Ac. 

 L. C, xxvii. (1860), p. 17 ; " and delete the words "et Oreaster 

 giffas." 



Correct page of reference to Liitken (1859) to "p. 64." 

 For " 1862, Oreaster tuberosus, Belm," — read " 1859, Oreaster 

 tuherosus, Mobius, Neue geesterne, p. 6, in Abhandl. Geb. Naturw. 

 (Hamburg), iv. p. 2. The specific name was suggested by Prof. 

 Behn." 



Complete reference to Agassiz, — "no. 9 (1869), p. 307." 

 The numerous names given to this species will afford some indi- 

 cation of its variability ; it will perhaps be most convenient to 

 commence with an account of a large almost perfect (though dried) 

 specimen. 



R is about equal to 2 r. Disk exceedingly high ; arms rapidly 

 tapering from their base, rounded, not cariuated, so that the lophial 

 line is very indistinct ; spines developed within the apical region. 



