142 



BULLETIN 106, UNITED STATES NATIONAL, MUSEUM. 



ALDERINA IRREGULARIS Smitt, 1872. 



1ST2. Meiiibranipora irrcgitlaris SMITT. Floridau Bryozoa. Kongl. Svenska Vetenskape- 



Akademiens Handlingar, vol. 10. No. 11. p. 8, pi. 11, fig. 63. 

 1914. Moiilirnnipora irrcyularis OSBUKN, The Bryozoa of the Tortugas Islands, Florida, 



Publication Carnegie Institution of Washing-ton. No. 182, p. 194. 

 Not D'ORBIGNY, 1839, WATERS, 1904, BUSK. 1S61, MANZONI, 1S75. 



Observations. We owe to the kindness of Doctor Osburn a very complete, 

 superb specimen of this interesting species, and we, are able to supplement, the 

 observations which are indispensable for its classification. The ovicell is transverse 

 and formed of two calcined layers; the superior one is very finely granulated, 

 incomplete, surrounding an area which is irregular and more or less linear. It is 

 hyperstomial and opens by a large special orifice which the opercular valve never 



closes. The latter is bordered by 



a vei T thick sclerite - The mu l 

 rim is granular and enlarged at 

 the base. This is a very well 

 characterized species of A Iderina. 



Measurements. (A0=0.34 mm. 

 Opesia ( ?0=0.20 mm. 



. [3=0.4:0-0.56 mm. 

 Zooecia' 



ife=0.30-0.40 mm. 



Affinities. This species is the 

 equatorial representative of the 

 boreal Alderina imbellis Hinck, 

 1860. It differs from it in its 

 transverse and nonelongated ovi- 

 cell and its irregularly linear and 



FIG. 36. Genus Alderina Norman, 1903. 

 A, B. Alderina imbellis Hincks, 1860. A. Zooecia, X 25. 



(After Hincks, 18800 B. Sketch showing dietellae, X 47. nonrectangular ovicellarian area. 



/ Aftor T d-i-incon IflUA 1 ~ 



(After Levinsen, 1894.) 



C. Alderina solidula Hincks, 1860. Ayoungzooeciumat 

 the edge of a zoarium. (After Norman, 1903.) 



Smitt in 1872 identified it 

 with Hfembranipora irregu- 

 laris D'Orbigny, 1839. The 

 type is no longer to be found at the Museum of Natural History of Paris. The 

 figure does not show an ovicell ; as the mural rim is smooth and is not enlarged at 

 the base, it certainly represents a different species from that of Smitt. Waters in 

 1904 J found it almost in the same regions; he figured its ovicell but without, giv- 

 ing its nature; the micrometric dimensions are much larger, to wit: A0=0.60 mm., 

 7o=0.32 mm., Zz=0.80 mm., fe=0.44 mm. If it should be proved that this is an 

 Alderina it would be necessary to rename Smitt's species of much later date. 



Busk in 1S61 - thought he had found D'Orbigny's species in the Madeira 

 Islands. The figure which he gives is in effect very close to that of the French 

 author; the mural rim is not enlarged at the base: this is. therefore, not the species 



1 1004. WatiTs. P.ryozmi, Result. Voyaire Brliiim X.uol.. p. :;i. pi. 11. fig. 6. 



-1861. Busk. Description of new Polyzoa. collected at Madeira in 1859 and 1860, Quarterly Journal 

 Microscopical Science, new ser., vol. 1, p. 77, pi. 33, fig. 3. 



