Vou. 2] Robertson.—Non-Incrusting Bryozoa. 265 
Bugula Oken. 
Cellularia Pallas, 1766. 
Bugula Oken, 1815. 
Cellularia, Johnston, 1847. 
Avicella Van Beneden, 1848. 
Avicella Van Beneden, 1849. 
Ornithopora d’Orbigny, 1851. 
Ornithoporina d’Orbigny, 1851. 
Bugula, Busk, 1852. 
Bugula, Hincks, 1880. 
Zoarivum erect, branched. Zoacia boat-shaped, or sub-quad- 
rangular, elongate, united in two or more series; aperture occu- 
pying a large proportion, sometimes the whole of the front, not 
turned upward or oblique. Avicularia in the form of a bird’s 
head, and jointed, usually one to each zowcium. Oacia sessile 
at summit of aperture, or pedunculate upon the side of the 
aperture. 
This genus is abundant in this region, not only in the number 
of species but also in the luxuriance of growth, and is remark- 
able for the large size which some of the species attain. Nine 
species are found, all of which are new except three; one, Bugula 
murrayand, is circumpolar, and another, B. neritina, is ecosmo- 
politan in range. 
KEY TO SPECIES OF BUGULA. 
Ji SUT OSCOMEY So ONISK Sta IES SES ew Lo ane 8 ae oe Bc epee ae J Ne 2 
The see OTE, ATO LES (ENE ESSA eA ae ee ed en Ue een 4 
2. Avicularia, if present, at summit of aperture -............... B. neritina 
Zee ASYM aT mete a SOMO Ap CL GUE Cyst ee rence ge ne ee B. pacifica 
2. Avicularia between summit and base of aperture =... 0... 3 
3. Avicularia much elongated, half as long as zowcium, slightly more 
than half way between summit and base of aperture 
Re ee os RE SN, Aon IRAE STi ee NE B. longirostrata 
3. Avicularia not elongated, less than half the length of a zowcium, just 
half way between base and summit of aperture....B. californica 
Ape AVLGTU RABY ap TSE ier teens 8 eR he eet ged ea EAs a RD 5 
cI a)a Nv CVU: Tose Bese] OYS(2) 01 ee ke, A a eee eo 2 B. laxa 
DaeAWwAeUl aria at baser Oh aOerbiut esse eee eee ee -B. murrayana 
5. Avicularia between base and summit of aperture _.............00...... 6 
6. Avicularia less than half way from base and summit of aperture........ 
BS eee eas oa. eee a ase ee eee eb. flabellata 
6. Avicularia near base of aperture, beak much curved _... 
poe SSE At at Bnad AO Seema BA Soang Mares Pete EN (Oe. tS Oe B. curvirostrata 
