PLATE XXIII. 



Fid. 1.- - l>rsnK-iilrni ki'iym Iriie/isis R. & D. var. antantii-n var. n. ; a, oxea (x 1BO) ; ft, side view; 

 ft 1 , front view of isochela ( X 1700) ; c, a variety with smaller palmate tooth (x 1700) ; J., il l , side 

 and front views "I isurhc'la from type of D. kerffuelenensis, R. & D. ( X 1760) ; p. ?>7. 



FIG. 2. Desmacidvn knyiirlrnenxis var. cactoidvs var. n. ; a, strongylate oxea ( x 160) ; ft, ft 1 , front and 

 side views of isorhelu ( X 17lio) ; p. 3H. 



Fie. .Desmacidon spinigera Kirkp. ; //, //, oxeas ( X 160) ; c, c 1 , side and front views of palmate isochela 

 (X 1760), p. 39. 



Fid. 4.Desntnri</on m,ii'ini,irhin Kirkp. ; /(, oxea (X 160); J-ft 3 , ancorae uuguiferae (X Too) ; p. 40. 



Fid. r>.('erntJiH-/if1,/ L;,ilH>xt/-ri Kirkp.; a, oxea (x 160); ft, c , d, f, ('anonochelae, developmental forms 

 (X 7(>0) ;/. lateral view showing lamellae (x 700); //, lateral view of side opposite to lamellae 

 (X 700); /, luM'k view, />., of the shaft, showing straight line of axial canal within the right 

 edge ( X 7i" i ; /, half of a spicule broken across ( X 700) ; /, end view ( X 700), p. 42. 



V\c,.C,.Ho t jl<ikillii/ra <lr<ii/i Kirkp.; , oxea (x 160); ft, spherostyles (x 160); ft 1 , spines on head 

 of ft (x 70o): <>~, |j nd view of a spine; c, r 1 , f 3 , side, front, and baok views of a fimbriated 

 placochele, p. 44. 



