388 



Plate IX. 



Fig. 1 a. Electro {Ilcleroofciiim) nmiileclens llincks. 

 with ocrcium. The small denticles are not 

 only seen at the margin of the membranous 

 area, but arc also visible through the ealei- 

 licd wall of the frontal surface. X 55. 



— lb. The frontal wall of the same species, from 



the internal surface. X 75. 



— 1 c. A variety of the same species. The lower- 



most zocvcium has been regenerated. X T.'i. 



— 2 a. Electni zoslrricold (Nordm.). The uppermost 



zooccium with odciuni. X 40. 



— '2 b. Two zoiecia of the same species. The up- 



per with ocecium. X 55. 



— 3 a. Calhiporn Dnmcrili (Aud.) Two developing 



occcia in difl'erent developmental stages. 

 X 55. 



— 4 a. Callopora attrila (Hincks). Uppermost a 



developing oiecium is seen, lowermost an 

 oci-cium in which the proximal part of the 

 ectooucium is not lakified. X 40. 



— 5 a-h. DilTcrcnt developmental stages of the 



ooecium and the covering avicularium of 

 TegclUi iiriicnrnis (Fh-m.). endo — the endo- 

 (xicium, ecto — the ectootecium. In fig. 5 d 

 the uniporous rosette-plates, destined to 

 connect the avicularium with the zoa'cium, 

 arc seen distally to the oiccium. In fig. 5 e 

 the first sign of the avicularium is seen as 

 a transverse ridge pro.vimally to the mem- 

 branous frontal area. In 5f — 5h the avicu- 

 larium. X 40. 



— 6 a-c. DilTcrcnt developmental stages of the 



Ott'cium and the covering avicularium in 

 Tegella SophUic [Uu&k). In Ob which is 

 younger than a) distally to the developing 

 orccium arc seen two oval incisions which 

 in fig. () a have closed themselves. It is the 

 beginning of the two rosette- plates which 

 should connect the avicularium with the 

 zoa'cium. Kig. (i c corresponds in the degree 

 of development of the avicularium with 



fig. 5 f. The two rosettc-platcs are seen. 

 X 40. 

 Fig. 7 a. Klectra bicolor l^llincks). X 55. 



7 b. The same species. Heproduction of a zoie- 

 cium. X 75. 



— 7 c. A transverse section through a colony. In 



two of the zoctcia the distal wall with 

 rosette-plates is seen, in two the immersed 

 cryptocyst. X 75. 



— 8 a. I'elalosiefiiis bicornis (Busk). X 55. 



— 8 b. A zoa'cium of the same species, seen a 



little more from the side X 55. 



— 9 a. Memhranii>orcll<i disUins Mac Gilliv. X 55. 



— 10 a. Two zo(ccia with oiccia of Cribrilinii annu- 



/((/<( iFabr*. The oiccia are covered by keno- 

 zorecia and on these some pore-chambers 

 are seen. X 40. 



— 10 b. A longitudinal section of the same species 



through a zoacium with o<i'cium. X 55. 



— 11 a-c. Three dilTerenl developmental stages ot 



the oa'cium of Crihrilina punctata Gray. 

 X 40. 



— lid. An oiccium of the same species. The endo- 



0(ccium is visible through the broken 

 ectooa'cium. X 40. 



— lie. The distal end of a zoacium of the same 



species with occcium. from the basal sur- 

 face. The porc-chambcrs of the zoa'cium 

 and kenozoacium are seen. X 40. 



— 11 f. rr/Vin/i/K/ /)(;/»■/(//((. I'ore-chambcrs are seen 



on the three marginal zocccia. of which the 

 central abnormal one has no aperture. X 55. 



— 1 1 g. The same species, from the basal surface. 



I'orechanibers (p. ch). X 40. 



— 11 h. .Sagittal section through a zoojcium of the 



same species with o<ccium. The oa'cium is 

 enclosed in a kcnozotccium. X 55 



— 12 a. I'licllina Cattijac (Husk), with oa-cia, from 



the basal surface. Uoth the zoacia and the 

 kcnozoa-cia enclosing the oa'cia are fur- 

 nished with pore-chambers. X 40. 



