284 MB. F. P. BEDFORD ON MALAYAK ECHINODEBMS. [Mar. 20, 



p. 518. P. de Loricl. Mem. Soc. Phys. &c. de Geneve, 

 t. xxviii. no. 8, 1883, p. 37. C. Ph. Sluiter, Natuurk. Tijd. 

 v. Ned. Ind. xlviii. 1889, p. 293. P. de Loriol, Rev. Suisse 

 de Zool. t. i. 1893, p. 375. 

 Locality 6f Habitat. Abundant in 5 to 10 fathoms on mud. 

 Singapore. 



Distribution. Extends from the East Coast of Africa to Fiji and 

 KiDgsmills Is. 



Adults are easi'y distinguished from L. decagonal* by the shape 

 of the test ; the young, however, approach each other rather closely 

 (v. tigs.) ; 5 genital pores usually visible. 



10. Laganum decagonale de Blainv. (Plate XXIII. figs. 

 6 a-e.) 



Laganum clecaqonum, L. Agassiz, Monogr. d'Echinod. ii. 1841, 

 p. 112, tab. 23. figs. 16-20. 



References. Alexander Agassiz, Revision of Echini, pt. 3, 1873, 



p. 520. F. J. Bell, Zool. Coll. of H.M.S. ' Alert,' 1884, 



p. 122. F. J. Bell, Ann. & Mag. Nat. Hist. ser. 5, vol. xi. 



1884, p. 130. F. J. Bell, Proc. Zool. Soc. 1894, p. 411. 



Locality Sf Habitat. Very abundant in 3 to 10 fathoms on mud. 



Singapore and Malacca. 



Distribution. Previously recorded from Japan, Prince of Wales' 

 Channel and Thursday Is., New Caledonia, and Bay of Bengal. 



The colour, when alive, is a dull red ; in spirit this first becomes 

 green, and ultimately disappears more or less completely. As shown 

 in the figures, the test is somewhat variable in shape, the angles 

 of the outline being somewhat less marked in young individuals. 

 The size of the genital openings varies considerably ; normally 

 there are four present, although occasionally the posterior pore also 

 occurs : in some specimens the genital openings are quite indis- 

 tinguishable even in the denuded test ; the extent to which the 

 coronal sutures are visible is also extremely variable. This species 

 is placed by Agassiz and others in the subgenus Peronella, but 

 Professor Bell (he. cit. 1883) has shown reasons for discontinuing 

 this mode of subdivision of the genus. 



Measurements. 



1. Length 66 - 5 mm. Diameter 63*5 mm. 



2. „ 57 „ 51 



3. „ 54 „ 49-5 



