Oso) -.. REPORT—1868. : 
Hymeniacidon sulphureus, Bow. “ Shetland, 1864” (Bowerbank in litt.). 
piupertas, Bow. Parasitical on zoophytes from deep water in 1861, off 
Out Skerries. 
Cliona celata, Grant. Common in shells. 
Halichondria panicea (Pallas). The encrusting forms very abundant in caves 
and on stones between tide-marks. A giant specimen, in the form of a 
roll wrapped round the stem of a Laminaria, measures 13 inches long 
and 3 inches in diameter, 
coalita (Grant). “Shetland, 1864” (Bowerbank in litt.). 
forceps, Bow. On the Outer Haaf, off Unst, in 1864 and 1868. The 
* forcepiform ” spicula in this species are very remarkable, and at once 
distinguish the species. They resemble very slender hair-pins, the bow 
very narrow, the pins very long, finely spinulous, and approaching each 
other at the points. 
simplex, Bow. ‘Shetland, Mr. C. W. Peach” (Bowerbank). 
incrustans (Esper). Abundant, coating the sides of Halse Hellyer, 
Burrafirth, growing side by side with H. panicea and Isodictya fucorun, 
the three species intermingling with each other. 
—— Dickiei, Bow. On Cellepora cervicornis, dredged in deep water, 1863. 
Patersonii, Bow. Rare, one specimen found in 1867. 
ct falcula, Bowerbank,n. sp. Sponge massive, sessile. Surface uneven, - 
minutely spinous and reticulated. Oscula simple, dispersed. Pores in- 
conspicuous. Dermal membrane pellucid, furnished with a stout irre- 
regular polyspiculous network. Skeleton—rete polyspiculous, very ir- 
regular and diffused ; spicula fusiformi-acuate, slender and long. In- 
terstitial membranes—tension-spicula same as those of the skeleton but 
smaller, few in number. Retentive spicula trenchant, contort, biha- 
mate, stout and large, very few in number. Gemmules membranous, 
aspiculous. Colour in the dried state cream-white. Habitat. Shetland. 
Rey. A. M. Norman. Examined in the dried state.” 
mutulus, Bowerbank, n.sp. Sponge sessile, massive. Surface 
openly reticulated. Oscula simple, very numerous. Pores inconspicuous. 
Dermal membrane spiculous; tension-spicula acuate, slender, very 
nearly as long as those of the skeleton, fewin number ; also tricurvato- 
acerate, very long and slender, nearly straight, sometimes flexuous ; 
central curve abruptly angulated or looped, rather numerous; retentive 
spicula dentato-palmate, equianchorate, very minute and symmetrical, few 
innumber. Skeleton equably reticulate ; rete stout and polyspiculous ; 
spicula subattenuato-acerate, stout and strong, moderately long. Inter- 
stitial membranes pellucid, furnished with the same forms of spicula as 
the dermal membrane but more sparingly. Colour in the dried state 
light brown Habitat. Shetland, 96 fathoms (Rev. A. M. Norman), 
Examined in the dried state.” 
scandens, Bow. The type specimen, dredged in 1861 in deep water 
off the Out Skerries. It is a minute species, which encrusts the stems 
of Sertularian Zoophytes. 
Batei, Bow. ‘Shetland?, Mr. Spence Bate” (Bowerbank). 
—— Hyndmanni, Bow. “Shetland, 1864” (Bowerbank in litt.). 
albula, Bow. “Shetland, deep water, Barlee ” (Bowerbank). 
mornata, Bow. “Shetland, Mr. C. W. Peach” (Bowerbank). 
Isodictya varians, Bow. ‘Shetland, Mr. Barlee” (Bowerbank). 
jugosa, Bow. The type specimen, found in deep water off the Out 
Skerries, 
ce 
