Prof. P. Martin Duncan — On Galerites alborjalerus, Lamk. 11 



and all regard the form as a toothed Echinoid, which it certainly is 

 not. Desor, Forbes, Cotteau and Triger, and Dr. T. Wright, F.R.S., 

 have written on this species, and I cannot agree with their statements ; 

 but Loven as usual is a master in exactitude, and there is only one 

 point of difference between us, and it is one which he rather avoids. 



Desor, in his " Synopsis des Echinides fossiles," gives the follow- 

 ing generic determination : — Galerites, Lamarck, 1801. Swollen 

 urchins, often conical, sometimes turrited, narrowed posteriorly. The 

 inferior surface flat. The peristome central elongated, but nevertheless 

 decagonal. The periproct infra-marginal. Tubercles small, slightly 

 close, indistinctly in series. Four genital pores. The odd posterior 

 plate (the 6th) is imperforate and sensibly smaller than the other 

 plates. The masticating apparatus is composed of vertical jaws. 

 The spines are in the shape of little smooth filaments and are 

 striated longitudinally. 



Galerites albogalerns, Lam. "Forme normale." A conical urchin 

 as high as it is long, slightly narrowed behind, with a level base. 

 Periproct infra-marginal. " Forme obtuse." A less elevated variety. 

 " Forme haute et coraprimee." " Forme pyramidale." " Forme 

 anguleuse ; " and " Forme mixte." These varieties speak for them- 

 selves. 



Desor's figures, op. cit. tab. xxv. fig. 5-10, show the different 

 shapes of the four varieties, indicate that the base on which the test 

 stands is perfectly flat, that the 5th or posterior generative plate 

 (No. 5) has a posterior angle which sepai-ates the postero-lateral 

 ocular plates, and that the pairs of pores of the ambulacra are 

 oblique and in equal-sized low plates. He shows the long narrow 

 teeth (after Forbes), and indicates that the actinal pairs of pores are 

 in quite straight series, the peristoraial (mouth edge) end of ambulacra 

 being rather broad. 



Forbes described Galerites albogalerns. and attributed the species 

 to Klein in " Memoirs of the Geol. Survey of the United Kingdom," 

 decade iii. plate viii. 1850. He did great service by grouping the 

 varieties of the species and by describing and illustrating a type. 

 It is not necessary to quote Forbes's description at length, but only 

 to refer to imjjortant parts of it. " The ambulacrals are minute, 

 and often cuneiform, and are separated from each other not infre- 

 quently by small accessory plates." " The base is flat. Its ambu- 

 lacral and interambulacral areas are studded with numerous spini- 

 ferous tubercles, larger than those of the dorsal surface. In the 

 foi'mer they form oblique rows of four, or at most five, across the 

 whole of each ambulacral space near the margin, and diminishing 

 in number towards the mouth ; in the latter they are thickly 

 crowded towards the margin, and ranged towards the mouth in 

 oblong transverse groups, interrupted by raised granulated wavy 

 spaces which mark the lines of junction of the plates, and forming an 

 arachnoid arrangement of irregular rings on the base, of which 

 the mouth is the centre." "The base is elongated, posteally 

 thickened, and subrostrated for the anus, which is large and broadly 

 elliptical in a longitudinal direction ; its margins are raised and 



