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any solid body would be at once caught and retained by the barbs.” It is, however, only in fresh specimens, or in those which have been at once put up in preservative, that these can be properly seen in their natural position; in the dried sponges they are so loosely attached as generally to become separated.

Amongst other forms to which we can only briefly refer, are many of delicate cruciform shape, much resembling the foot pieces of the spicules last described. Some are large and present the appearance of four radii springing at right angles from a central axis, hexradiate. We also find a number of peculiar kedge-like forms, some very simple, others larger, passing through various gradations of size, but leading up to the magnificent spicule described in scientific terms as “multihamate birotulate, shaft slight, cylindrical, papillate.” It might be roughly compared at first glance to two open umbrellas made of the finest spun glass with their sticks fused into one, but the true structure of the expanded portion is shown here, delicate silicious leaves curving gracefully from each extremity of the shaft towards its centre.

There are many other forms of spicules to reward the painstaking microscopist who searches for them, some of them minute and requiring the higher powers of the instrument and careful examination of the lighter washings, but the most beautiful and distinctive are those which we have seen and which can be easily demonstrated with the most ordinary microscope.

In conclusion, I would venture to impress upon you that there is a great deal yet to be discovered concerning this very interesting and curious sponge, which can only be learned by the careful examination of fresh specimens in the natural condition in which they are brought up from their ocean bed, and it is chiefly with a view of enlisting amongst the ranks of the observers any of my hearers who may be passing a holiday at Enosima or the neighbourhood from which the sponges are brought, that these few brief notes of the Hyalonema are brought before your notice. The discovery, for example, of a young specimen complete