348 



of (respectively ca. i — 6 and 3^4) small, uniporous rosette-plates. The colonies 

 are incrusting and superficial budding occurs in most. 



Whilst s])incs never occur in any member of the family Celleporklac, such are 

 found on the other hand in a number of species of this family to a number of 

 2 — 6, e. g. in » Cellepora<< apiculata Busk, C. trulenticiilatu Busk, Cellepora brimnea 

 Hincks, C. verrucosa Mac Gill., C. hicirrhata Ortni., C. triacantha Ortm." and Dis- 

 coporai aduena Smitt. The aperture has a concave or straight proximal margin, 

 and though this in very rare cases may have a slight, rounded incision centrally, 

 it cannot be compared with the sinus in Cellepora. This sinus is in reality the 

 interspace between the two hinge-teeth or the two corresponding places of sus- 

 pension for the operculum, whereas in the species mentioned as in all the other 

 species of the family Holoporellklae, the hinge-teeth or the corresponding places 

 of suspension for the operculum are situated on the lateral margins, which are 

 well-separated from the proximal margin. Another difference lies in this, that this 

 excision is not as the sinus in Celleporulae occupied by an opercular tongue. Such 

 a small, rounded incision is found for instance in 'Schiznpnrelld' aperta Hincks, 

 which belongs in reality to this family. In not a lew species the proximal maigin 

 of the aperture is provided with a row of 3 — 6 teeth of varying form but usu- 

 ally high or narrow, all of which are situated outside the operculum, so that 

 none of them can be compared with hinge-teeth. Such teeth, which presumably 

 serve to protect the operculum, are found in C. liiherciilata Busk, C. honoliilensis 

 Busk, C. Jachsoniensis Busk, C. tridenticiilata Busk, C. pohjmorpha Busk, C. serrati- 

 rostris Mac Gill.', C. hicirrhata Ortm.-, C. transversa Orlm.'~ and 'Discopora^ ad- 

 vena Smitt. 



The oa^cia, which occupy the greater part of the margin of the aperture, are 

 widely open, have no pores and consist only of a single calcareous layer, which 

 seems to lack a covering membrane; but as the ooecia-bearing species I have 

 been able to examine were almost all dry specimens, I cannot determine this 

 question with certainty. If a covering membrane is really lacking, they must i)ro- 

 bably be regarded as peristomial, but in any case they are veiy dillerent from 

 the ooecia in the Celleporidae. Good drawings of such ooecia are seen in Hincks' 

 figures of ySchizoporella<!^ aperta-' and ^Monoporella<^ albicans^ and in Waters^ 

 figure of Holop. Descostilsi And. Superficial budding occurs in this family just as 

 in the family Celleporidae, and the rosette-plates therefore only occur in the 

 basal zooecial layer. The zooecia in this family in contrast to the foregoing have 

 a rectangular circumference, and both the distal wall and the distal half of each 



' 68, p. 114. ' 87, p. 55. ' 26, p. 126. * 26, p. 123. ^ 116 a, p. 162. 



