PORIFERA. I. II 



Atlantic coast of America it is found from Florida to Labrador (Carter, Lambe, \'erril). It is further 

 enumerated as found in the ba>- of Bengal, the Mergui archipelago (Carter, var. fibrosa^ this deter- 

 mination, however, is likeh- to be doubtful), and finally with regard to Polynesia from the Fidji Islands, 

 New Zealand and the Auckland Islands south of New Zealand (Lendenfeld). Thus the species is spread 

 from 63' 20' Lat. N. to about 50' Lat. S. Its bathymetrical distribution reaches from shallow water, 

 about 4 fathoms to about 80 fathoms, which seems to be the largest depth, in wliich it has hitherto 

 been taken. 



2. Ch. spatula u. sp. 



PI. II, Fig. 3, Pi. VIII, Figs. 8—9. 



Leaf-shaped or spattilate, stipitate, the blade oval. The fibres form a regular skeleton of longi- 

 tudinal fibres and transverse fibres zuith quadratic meshes. The fibres almost e.xclusively nnispicular, 

 the transverse fibres consisting of single spicules connecting the primary fibres. Only little spongin 

 forming no visible sheath. Irregularly running., polyspicular longitudinal fibres ivith more spongin 

 are present. The surface finely sliaggy from projecting spicules. Oscula liave a somezi'hat projecting 

 edge, they are spread arid found on both sides. Spic?tla oxea o-tg—o-22""". 



This species has a fine and regular form like an erect, oval leaf running below into a stalk 

 passing evenly into the leaf. The height is full 14"", of which ca. 6"" may be put down as stalk; the 

 largest breadth of the blade is 65""". Below the stalk is cylindric, and passes b}- degrees into the flat 

 blade. The thickness of the stalk in the middle is ca. 8™™; the blade is thickest below, and has here 

 a thickness like that of the stalk, 8—9""", in the middle its thickness is ca. 6""". The nether half of 

 the margin of the blade where the transition from the stalk is still felt, is rounded, while in the upper 

 half part it is drawn out to a rather sharp edge. The colour (in spirit] is whitish yellow. The con- 

 sistency is elastic, but the sponge is rather soft. The surface is smooth, but finely shagg\- from the 

 projecting spicules. The dermal membrane is very thin and transparent, and rests on the skeleton 

 below, the ends of the primar> fibres projecting through it. When the sponge is seen in spirit the 

 ver\' close-set round subdermal cavities or mouths of the incurrent canals shine through the skin; 

 the\- have on an average a diameter of i"""; in some places they are seen to be incompletely separated, 

 so that the\- run into one another and form irregular lacunae. Oscula are spread on both sides of the 

 sponge, a single one is placed quite at the edge; they are also found on the stalk down to the lower 

 third part of it; the>- are circular openings with an average diameter of 3"""; their margin is some- 

 what projecting, so that they have a sharp edge; the canal into which the>- lead, does not run hori- 

 zontally inward, but obliquely downward, and therefore oscula do not point horizontally outward, but 

 a little obliquely upward, so that the margin is most projecting at the lower edge of the oscular 

 aperture. The pores are situated in the thin dermal membrane; they are round or roundish holes of 

 \er\- varving sizes measured from o-oii — o-27"'™. They are found on both sides of the sponge, and 

 continue also down on the stalk. In most places the pores are placed close together; they often 

 reduce the membrane to a network, so that the pores are only separated by thin strings of tissue; in 

 such cases they get an irregular polygonal form, and may get a still greater size than the measures 

 given. When a piece, cut off parallel to the surface, is examined under the microscope, the skeleton 



