NORTHUMBERLAND AND DURHAM. 231 
smooth, a little undulating, and slightly wrinkled on the 
lower part; the stems united together by reticulated creep- 
ing tubes at the base. Polypes, slender, retractile, with 
eight long muricated tentacles, held alternately up and 
down. Gonophores, pear-shaped or sub-globular, set two 
or three together on the stem of the polypary, each cap- 
sule containing a single medusoid. Height a quarter of 
an inch. 
Medusoid globose, slightly truncated below, with a con- 
tracted aperture. Four moderately sized, sub-clavate 
tentacles arise from four semi-circular yellowish lobes, at 
the margin of the umbrella ; sub-umbrella small, with 
four radiating canals, the centre occupied by a mass of 
yellowish or orange granules, apparently ova ; peduncle 
inconspicuous, branched at the base. 
On Turritella communis, Astarte Danmonie, and other 
shells from deep water, Cullercoats. 
This species has considerable resemblance to A. repens, but 
its polypary rises much higher, is proportionately more slender, 
and not so much expanded at the aperture. In the young state, 
however, it is difficult to distinguish them. Their medusoids, 
nevertheless, are very different, and prove them to be distinct 
species. I have never seen A. linearis branched, though it is 
possible it may occasionally be so in luxuriant specimens. 
3. A. aArENosA, n. sp. Pl. IX., fig. 5—7. 
Polypary, vainute, consisting of a creeping fibre, from which 
arise short funnel-shaped tubes, rather irregular in form, 
but always expanding more or less at the top, from which 
the polypes issue; generally covered with minute grains 
of sand. Polypes entirely retractile, with long, slender, 
muricated tentacles, varying in number according to age 
from six to twelve. 
On the under side of stones and the roots of Laminaria, at 
Tynemouth and Cullercoats, occasionally. 
All the hitherto described Atractyles are propagated by medu- 
soids, but this species proves to be an exception, as Dr. Wright, 
