EXPIANATIOW 01' THE PLATES. 673 



Eig, n. Toxochalina robusta, portion of skeleton, showing primary 

 and secondary fibre, n'. Skeleton acerate and tricurvate 

 acerate spicules, x 370. Prom type specimen from Port 

 Jackson. 



0. PacJiychalina maerodaetyla. Skeleton-spioule, x 190. 

 From specimen figured Plate XL. fig. B. 



p. Protosehmidtia hispidula, portion of vertical section, x 

 68. p'. Skeleton-spicule, x 190. From type specimen 

 from Albany Island. [Note. — Some loose spicules in tbe 

 interspaces of the skeleton have been omitted for the sake 

 of clearness.] 



q. EJiizochdlina sjpathulifera. Skeleton-spicules, X 68. From 

 type specimen from Thursday Island. 



r. B. canalis. Skeleton-spioule, x 68. From type specimen 

 from Port Darwin. 



s. E. singaporensis, var. Spicules, x 190. From specimen 

 from West Island, Torres Straits. 



t. Sehmidtia variabilis. Spicules, x 68. From type specimen 

 from Port Darwin. [The median curve of the diagonally- 

 placed spicule is represented as too sudden, and the two 

 lateral curves introduced do not exist.] 



u. Meniera testudinaria, part of vertical section, X 38. «'. 

 Spicules, X 68. From dry specimen from Port Denison. 



v'. Pellina muricata. Skeleton-spicule, with ends of two 

 others, exhibiting the wide range of variation, x 190. 

 From type specimen from Port Darwin. 



w. P. alifortnis. Skeleton-spicule, x 68. From type specimen 

 from Port Darwin. 



X. P. eusipTionia. Skeleton-spicules, x 68. From type speci- 

 men from Port Darwin. 



y. ^mphileetus hispidulus, vertical section, x 68, y'. Skeleton 

 acuate spicule, x 190. y". Anchorate spicule from front 

 and side, x 370, From type (dry) specimen from Thurs- 

 day Island. 



2z 



