8-i< PLATE xxxiir. 



Hymeniaoidon macilenta, Bowarhank . 



Fig. 7. — Three specimens of tlie species from the 

 Island of Herm, by tlie Rev. A. M. Norman. Natural 

 size. 



By an oversight of the artist the skeleton spiculum 

 of this species has been omitted in the Plate, but it so 

 hajopens that the skeleton spiculum of Htjmeniaciclon 

 fcdlax, represented by fig. 17 in the same plate, is of 

 the like form and proportions as that of H. inacilenta. 

 I must therefore refer to that figau^e as a sufficient 

 representative of the skeleton spiculum of the species 

 in course of description. 



Fig. 8. — One of the sub-clavate, acuate, slender, 

 dermal, tension spicula. X 150 linear. 



Fig. 9. — One of the slender, tricurvato-acerate, 

 tension sjiicula of the dermal membrane. X 1-50 

 linear. 



Figs. 10 and 11.' — Two of the contort-bihamate reten- 

 tive spicula. X 150 linear. 



Fig. 12. — One of the inequi-dentato-palmatc reten- 

 tive spicula of the dermal membrane. X 530 linear. 



Fig. 13. — An inequi-bidentate, retentive, spiculum 

 from the dermal membrane. X 530 linear. 



Hymeniacidon vakiantia, Bo'wcrhaiik. 



Vol. ii, p. 174, ' Mod. Brit. Spongiada,'." 



Fig. 14. — Represents the type-specimen of the 

 species. Natural size. 



The spicular illustrations required more space than 

 could be assigned to them in the plate in which the 

 sponge is figured in the order in winch it is arranged 

 in vol. ii. They will be found as follows in plate XLV 

 of this volume. 



