80 
MOLLUSCA. 
Cirrus. 
Genus XXXVI—CIRRUS— Sowerby. 
Spiral; conical; with a hollow, funnel-shaped axis; 
volutions contiguous, numerous, rounded, or slightly 
angulated. 
The shells of this genus nearly resemble those of 
Troclius , but may be distinguished by their funnel- 
shaped umbilicus. 
1 . C. nodosus. —The Knotty Cirrus, pi. XLI. fig. 9 and 21. 
Cim'us nodosus, Sowcrby, Min. Conch. III. p. 35, pi. 219, 
fig. 1 and 4. Ib., II. p. 94, pi. 141, fig. 2, a cast. Fleming, 
Brit. An. p. 313. 
Shell conical, rugose, reversed, acuminated; body large, dis- 
coidal, in diameter, occupying not quite a third of the entire 
length of the shell; spire acutely conical, consisting of ten or 
eleven flat-sided volutions, separated by a narrow suture, with 
two rows of lengthened tubercles, and crossed by many small 
carinse; body with four series of spiral, undulous carinae, which 
are crossed by numerous lengthened tubercles; between the 
transverse carinac are fine, regular, elevated striae, which are 
very conspicuous on the lower portion of each volution. 
Found in the Inferior Oolite, Dundry. 
Fig. 21 is a cast of the shell. 
2 . C. Leachii. —Leach’s Cirrus, pi. XLI. fig. 19* 
Cirrus Leachii . Sowcrby, Min. Conch. HI. p. 36, pi. 219? 
fig. 3. Fleming, Brit. An. p. 313. 
Conical; with numerous longitudinally striated volutions, pro¬ 
vided with several rows of tubercles, crossed by numerous small 
carinse; the superior row of tubercles on the body volution 
crowned with slightly arcuated, strong compressed spines. 
Found in the Lower Oolite at Dundry. 
3. C. turbanoiDes. —The Turbanated Cirrus, pi. XLI. 
fig. 24. 
Cirrus nodosus, var . Sowerby, Min. Conch. III. p. 35, pi. 
219, fig. 2. 
Shell reversed; with the body volution discoidal, above which 
the spire rises into a flattened cone; the four or five superior 
volutions abruptly conical, and terminating in a rather acute 
apex ; the whole surface covered with divergent ribs, which do 
not, however, extend to the four or five superior volutions; 
aperture subovate. 
Found in the Lower Oolite at Dundry. 
4. C. pent ago nalis —The Pentagonal Cirrus, pi. XLI. 
fig. 16. 
Cirrus pentagonalis . Phillips, Geo. of Yorkshire, II. p. 
226, pi. 13, fig. 8. 
Shell conical, obtuse; body large; spire short, with subpenta¬ 
gonal volutions; base flattish, with an acute margin; umbilicus 
large, deep, with an acute margin; aperture subovate, trans¬ 
verse, descending; outer lip thin; inner lip reflected on the 
columella, but not intruding upon the umbilicus. 
Found in the Mountain Limestone at Bolland. 
5. C. spiralis. —The Spiral Cirrus, pi. XLI. f. 18. 
Cirrus spiralis. Phillips, Geo. of Yorkshire, II. p. 226, pi. 
13, fig. 14. 
Shell obtusely conical; body large; spire short, consisting of 
three moderately rounded volutions, terminating in a sub-acute 
apex; base rounded; whole surface covered with strong, spiral, 
and longitudinal nearly obsolete, oblique strise. 
Found in the Mountain Limestone at Bolland. 
6. C. pileopsideous. —The Cap-like Cirrus, pi. XLI. fig. 
22 . 
Cirrus pileopsideous. Phillips, Geo. of Yorkshire, II, p. 
226, pi. 13, fig. 6. 
Shell considerably depressed; body very large; spire small, 
consisting of three flattened volutions; whole shell covered 
with irregular, somewhat arcuated strise. 
Found in the Mountain Limestone at Bolland. 
7. C. cingulatus. —The Small-girdled Cirrus, pi. XLI. 
fig. 17. 
Cirrus cingulatus . Phillips, Geo. of Yorkshire, I. p. 107, 
pi. 4, fig. 28. 
Shell subconic, subdepressed, somewhat turban-shaped; body 
and spire of about equal length; spire with spiral and longitudi¬ 
nal striae; each volution with a smooth girdle at its upper part; 
body with many longitudinal, arcuated smooth bands; base 
rounded ; apex obtuse. 
Found in the Lower Calcareous Grit at Scarborough; and is 
in the cabinet of Mr. Bean, by whom it was discovered. 
8. C. plicatus. —The Plicated Cirrus, pi. XLI. fig. 20. 
Cirrus jjlicatus. Sowerby, Min. Conch. II. p. 94, pi. 141, 
fig. 3. 
Shell conical; body large; spire small, consisting of four flat¬ 
sided volutions, w r ell divided by the suture; the whole shell 
with pretty wide spiral striae; base somewhat angular, and its 
diameter a little more than the length of the shell; aperture 
subquadrangular, its width exceeding its length; umbilicus 
plaited, and rather small. 
Found at Folkstone. 
9. C. acutus. —The Acute Cirrus, pi. XLI. fig. 23 and 25. 
Cirrus acutus . Sowerby, Min. Conch. II. p. 93, pi. 141, 
fig. 1. 
Shell conical; body large; spire short, consisting of six or 
seven somewhat ventricose volutions, with an obscure carina 
near the upper part of each, and terminating in a rather acute 
apex; base rounded; umbilicus funnel-shaped, expanding; aper¬ 
ture orbicular ; surface with fine, regular lines of growth. 
Found in the Limestone, Derbyshire. 
10. C. rotundatus. —The Rounded Cirrus, pi. XLI. fig. 
24 and 27. 
Cirrus rotundatus. Sowerby, Min. Conch. V. p. 36, pi. 
429, fig. 1, 2. 
Conical, smooth; volutions convex; base rounded; umbilicus 
large, with an orbicular aperture; lines of growth fine; height 
and diameter of base nearly equal. 
Distinguished from C. acutus y in being devoid of the flattened 
portions on the upper surface of the volutions; and in its general 
aspect has a bluntness, which serves to characterise it. 
Found in the Limestone of the Lead measures, near Settle, 
Yorkshire. 
11. C. tabulatus. —The Boarded Cirrus, pi. XLI. fig. 28. 
Cirrus tabulatus. Phillips, Geo. of Yorkshire, II. p. 226, 
pi. 13, fig. 7. 
Shell subconic, depressed; volutions few, subquadrate, tabu¬ 
late, or concave above, with flattened sides, and their upper 
margins acute; aperture transverse, and ovate. 
Found in the Mountain Limestone of Kendal, Bolland, and 
Northumberland. 
