558 W. WOODLAND. 
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Journ. Mic. Sci.,’ vol. xl, 1896. 
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EXLANATION OF PLATES 32, 33 & 34, 
Illustrating Mr. W. Woodland’s “ Studies in Spicule- 
Formation.” 
With the exception of Figures 25—30 and 43, 44, all have been drawn with 
a magnification of 750 diameters. 
PLATE 32. 
Development of the (2) variety of spicule in Cucumaria sp. 
Fic. 1.—Free scleroblasts. 
Fic. 2.—Division of the scleroblast. ¢ is apparently an association of two 
scleroblasts. 
Fig. 3.—The initial calcareous granules. 
Fic. 4.—The spicular needle. a@ and d biscleroblastic, ¢ tetrascleroblastic 
in origin. 
Fies. 5, 6, 7.—Growth of the young needle. In Fig. 7 the rod is tetra- 
scleroblastic in origin. 
Fic. 8.—Initial broadening and bifurcation of the rod. In ¢ one of the 
cells has divided. 
Fic. 9.—Bifurcation of the rod. a, 4, and ¢ are biscleroblastic, d, e andy 
tetrascleroblastic in origin. 
Fie. 10.—Second series of bifurcations. a and & biscleroblastic, c and d 
probably tetrascleroblastic in origin—probably because the two primary 
scleroblasts may have divided. 
