16 Miss B. B. Crozier on Bermudian 



periphery of which they form a dense sheet ; in addition to 

 the usual tylote form there are some with oxeate aetines. 

 (4) The oxyasters, as contrasted with those of D. sey- 

 chellensisy are commonly bent, evenly curved, or branched ; 

 they are very abundant throughout the choanosome, but 

 relatively sparse in the cortex, especially its outer layer. 



Though most abundant upon the eel-grass of tidal creeks, 

 where it assumes a spherical form, D. ingalli variety A has a 

 wider distribution in Bermuda waters than has D. sey- 

 chellensis, and its form is modified to suit the various localities 

 in which it occurs. Numerous specimens have been found 

 attached to stones along the shore of Agar's Island at low- 

 water mark, and these are usually flattened at the base to 

 present a large area of attachment. In extreme cases the 

 sponge is reduced to a hemisphere, or even grows over the 

 edges of small stones, to irregularities in the surface of which 

 it conforms. The anchoring filaments, which appear in 

 D. seychel/ensis as slender fibres usually but two in number, 

 are here heavy strands or even thick sheets, which grow out 

 from the base of the sponge over its substratum. These 

 sponges have been collected also from stones along the shores 

 of Hungry Bay; while from the shore of Long Island and 

 neighbouring islands have been obtained the largest specimens 



1 have ever seen. They were attached by heavy anchoring 

 strands to the vertical faces of rocks and at depths down to 



2 fathoms, as contrasted with the very shallow positions in 

 which all other specimens have appeared. This sponge has 

 been much more frequent than D. seychellensis throughout 

 the winter, but very sparse and lacking in buds as compared 

 with its profusion and activity during the autumn months. 

 In May it has been found in fair abundance, but with few 

 bills, in the tidal creeks, not raised upon the eel-grass, but 

 resting on the muddy bottom and upon dead shells. 



Variety B. — Though the two varieties of I). ingalli are 

 identical in most of their important anatomical characters, 

 they are readily distinguished in their natural situations by 

 their different external appearance ; a few constant anatomical 

 differences also permit one to distinguish between them after 

 preservation. In the tidal creeks, on stones at low-water 

 mark, and on the vertical faces of rocks at 2 fathoms depth, 

 variety B occurs with variety A in about the proportion of 

 1 to 12. Its autumn budding-season coincides with that of 

 variety A, and it is likewise fairly abundant upon the muddy 

 bottoms of tidal creeks in early summer ; but in this latter 

 situation its degree of budding is noticeably greater than that 



