Plate 49 



Fjg. 1. Gellitis varius. var. fibrosa. From a vertical section, showing part of 

 skeletal reticulum including two radial fibers, r. /., with connec- 

 tives, c, X3."i0. 



2. Petrosia crustata. Spicules. X375. 



3. Myxilla erucifcra. a. skeletal style; b, ectosomal tornote ; C, sigmas 



in two positions. X240. 



4. Myxilla crucifera. Ancoras (tridentate isancoras). a, side view; b, 



ventral view. X1100. 



5. Lissodendoryx tawiemix. a, skeletal style; b, ectosomal tylostrongyle ; 



c, toxa: d, isochela. a, b, c, X240; d X 1,100. 



6. Coelosphaera toxifera. a, the two ends of a typical strongyle ; b, 



one of the very small strongyles ; e, isochela; d, toxa. X400. 



7. Clathria fa&ciculata. Style of the skeletal fiber and echinating acan- 



thostyle. basal end of the latter buried in the spongin of the fiber. 



X400. 

 S. Clathria fazcieulata. a, b, large and small dermal styles. X400; c, 



isochela. X 1,100. 

 9. A.rinij$$a nculcata. From a vertical section, showing two dermal 



eonuli with included spicules. X60. 



10. Theonella sicinhoei, var. verrucosa. Phyllotriaenes seen from below. 



X90. 



11. Theonella irwaginata. Nearly the whole of an isolated, not fully 



developed, desnia. X210. 



12. Theonella invaginata. Dermal phyllotriaenes. X100. 



13. Theonella invayinata. Gastral phyllotriaenes of a less modified type 



than those of tig. 14. X.100. 



14. Theonella invayinata. Gastral phyllotriaenes. X100. 



15. Theonella invayinata. Part of a fully developed desma. X210. 



519 



