PROGRESS OF MICROSCOPICAL SCIENCE. 
45 
advantage results from the manipulator being himself a mycologist, 
consequently the preparations are scientifically and accurately named, 
to say nothing of the neat and business-like manner in which the 
mechanical work of manipulation is performed. Here, then, is an 
excellent opportunity for anyone to possess themselves of illustrations 
of the principal genera of microscopical fungi, any such a series being 
manufactured to order. We are also further informed that anyone 
who is desirous of doing so may have their own material mounted, 
so that nothing more remains to be desired, except it be a reasonable 
and economical scale of charges, which, in this instance also, will bo 
found entirely to their satisfaction. We can only hope that such 
invaluable aids to the study of fungi will not be neglected, and that 
Mr. Yize’s unique and artistic preparations will find a place in every 
microscopical cabinet, whether specially devoted to mycological 
subjects or not.” 
The Spongilla jluviatilis . — Although the development of this species 
has been worked out before, Mr. Fullagar’s researches are not without 
interest. ‘ Science-Gossip’ for June says that, at a recent meeting of 
the East Kent Natural History Society, Mr. Fullagar (who has been 
successful in getting it to live and grow in confinement) again ex- 
hibited the fresh-water sponge ( Spongia jluviatilis), illustrated by 
diagrams, showing (since the last meeting, December 6) the pro- 
duction by growth of the pellucid, semi-transparent, gelatinoid 
substance termed sarcode, which had extended to some distance on 
the glass cell in which it was placed ; in the new sarcode the pores 
through which the current of water enters the sponge were observable, 
forming the in-current, bearing with it the nutriment on which the 
sponge feeds. In the newly formed sarcode was to be seen a number 
of new spicules ; they were pointed at each end, and their middle or 
centre was bulged out, from which the growth extended to both 
terminal points ; the mature spicules are a little bent or curved, and 
pointed at both ends, but not bulged out in the middle. Some good 
specimens of the mature spicules have been cleaned and mounted by 
Mr. Hammond. They are composed of the pure silex, as transparent 
as glass. The peculiar spicules of the ovaria were beautifully shown 
under the microscope. In a specimen Mr. Fullagar had successfully 
mounted in dammar, by first drying the ovaria, and then in a drop of 
dammar with a thin glass cover gently pressed down, the granular con- 
tents of the ovaria were pressed out, and the beautiful stellated form 
of the spicule was seen standing out in form of so many miniature 
palm-trees : the real form of them is stellated at the two ends, con- 
nected together by a shaft, similar to two wheels on an axle. This 
form of spicule in the ovaria performs the double office of tension and 
defence. 
