6 MAZATLAN BRYOZOA 
The wide, rounded or elliptical raised margin of the mouths 
of the distant cells gives the polyzoarium of the present species 
a very peculiar and well marked aspect. It is of a brownish 
hue, or white. 
Hab.—Mazatlan ; on Imperator unguis; L’pool Col. 
Tablet 15 contains a group on Imperator.—l6, a group de- 
‘tached. 
Susorper II. CYCLOSTOMATA. 
FAMILY DISCOPORADA. Busk, (ms.) 
Genus DEFRANCIA, Bronn. 
13. Derrancia IntRIcCATA, Busk, (n. s.) 
Disco valde irregulart ; irregulariter radiatun costulato ; ori- 
Jicits tubulorum, porisque interstitialibus equalibus magnitudine. 
The small irregular patches appear to be constituted by the 
confluence of several sets of coste with their corresponding 
interstices, each set radiating from a depressed central point. 
It differs from D. deformis Reuss, (L. c. p. 36, pl. 5, f. 24,) in 
the uniform size of the openings of the tubes in the coste and 
of the pores in the insterstices. 
HTab.— Mazatlan ; on Imperator unguis; L’pool Col. 
Tablet 17 contains a group on Imperator. 
—-—— 
Besides the above, there occur on some of the shells, indica- 
tions of other species, but in too imperfect a condition to allow 
of their determination. Among these perhaps the best marked 
is a species strongly resembling Cellepora pumicosa, Lin., a 
species of Lepralia, and of Tubulipora. 
CLASS TUNICATA. 
Omnia adhue ignota, 
