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Show 1880.] PROF. F. J. BELL ON THE TEMNOPLEURIDAE. 431 their tips; the upper ones are banded with brown, those near the ambitus with purplish brown ; those around the actinostome are flattened, and the bands become distinctly purple, while the green is evanescent. The denuded test, though not unlike that of S. bicolor, is distinguished from it by its depressed actinostome, the greater height of the ridges connecting the auricles, the somewhat narrower ambulacral pore-areas, and the more distinct sutural pores. The changes during growth in the proportional size of the actinostome are somewhat striking; and I regret that it is only in the lately acquired specimens that the abactinal and anal areas are complete, so that it is impossible to trace the changes which occur in this region. Prof. Agassiz's specimens seem to be in a somewhat similar plight; for he is only able to give the measurements of the abactinal and anal systems of one of his specimens ; the percentage value of the abactinal area in the specimen measured by him is 18*5. The great changes in the proportions of the actinostome point to the necessity of carefully examining a series of forms before using the size of this orifice as a specific character. ii iii iv Absolute diameter in millims. 14 17 45 59 Percentage value of Height. 59-2 649 51*1 45-7 Abactinal area. 221 23*5 Anal area. 12-5 11-7 .Actinostome. 42-8 41-1 25-4 26-6 It may be of interest to point out that there is in the Museum collection a specimen which, resembling very closely the S. conica of von Martens, appears to bear out the view of Prof. Alex. Agassiz that S. conica is synonymous with 5. sulcata. Von Martens's specimen measured 72 millims. in diameter and 55 millims. in height, thus giving the latter a percentage value of 76*3 ; the specimen now under description had a diameter of 77 millims., and the percentage value of the height, abactinal and actinal areas, were respectively 65, 15*5, and 22. Some link is yet wanting to connect with these conical specimens of S. sulcata a specimen from an unknown locality, the height of which is 91 per cent, of the diameter, and which hardly conforms, in some other points, to the ordinary specimens of this species. 5. SALMACIS GLOBATOR. Two distinct species appear to have been described under this head-one by Agassiz & Desor, in the Catal. Raisonne (Ann. Sc. Nat. (3) vi. p. 359), the other by Prof. Alex. Agassiz, in the « Revision of the Echini' (iii. p. 473). One point will suffice to |