Miscellaneous. 245 



tion ; whilo S. Macl>:ayi and H.^ictovensis had previously been known 

 only from the discoveries of Mr. MacKay in Nova Scotia. 



One other form remains to be described, and at the suggestion of 

 its discoverer it is hereby designated 



Spongilla novce terrce, n. sp. 



Sponge incrusting ; sarcodo of the young growth a dense mass of 

 minute spherical cells, imbedding slender curving lines of fascicu- 

 lated skeleton-spicules, developing later into a very loose, open tissue, 

 with few connecting spicules. 



Gemmules rather numerous, unusually large, spherical ; chitinous 

 coat thin ; " crust " apparently wanting. 



Skeleton-spicules relatively few, slender, cylindrical, smooth or 

 sparsely microspined ; graduallj'' pointed. 



Dermal or flesh-spiciales very abundant, minute hirotidates of un- 

 equal size ; shafts slender, cylindrical, occasionally spined ; outer 

 surface of rotules dome -shaped ; rays prolonged, terminations acute ; 

 malformations frequent. Mixed with occasional linear, spined 

 spicules. 



Spicules upon the gemmula) abundant, crossing each other upon 



the crustlcss, chitinous body. 



. K n Their shape when smooth is 



\v \\ \v jj /^ f^ robust-fusiform, with pointed 



2^ \ '~\r "^ ^ "7% terminations ; the great ma- 



^"^ ^- ^ i^^"i^3'' however, have from 



'^ V^ ■?'' /? 'T^ one to six or more long spines 



•^j^ ^^ ^ '^ IX ^ ^^ non-symmetrically placed, 



"" ^ but with an evident tendency 



to group themselves at points 



about one fourth the length 



of the sjiicule from one or 



both of its extremities. 



Measurements : Diameter 



of gemmules 0-036 inch, 



skeleton-spicules 0*0068 by 



0-0002 inch ; length of average dermal spicule 0-00066 inch, of 



gemmula spicule 0-00145 inch. 



Habitat. Incrusting stones in shallow water. 

 Locality. Lakes or ponds in the vicinity of Heart's Content, New- 

 foundland, collected by Mr. A. H. MacKay. 



All the specimens of this sponge came from the neighbourhood of 

 Heart's Content, but whether they were gathered Irom a lake upon 

 the heights or from a brook mentioned by Mr. MacKay near the 

 sea-level does not seem entirely clear. The accompanying illustra- 

 tion (magnified 225 diameters) will suggest the peculiarities of its 

 skeleton, dermal and gemmular spiculation. The striking resem- 

 blance of the dermal spicules to the minute birotulates, heretofore 

 only known in a corresponding position in the case of Meyenia 

 Everetti, will at once impress the student. These are, however, 



