that Hagenow's division only embraces freely growing species it is founded on the 

 examination of a few badly conserved species of which only a single Eschariles gra- 

 cilis with certainty can be referred to the Eleidce, and as species belonging to this 

 division have never been found in the tertiary formation the following statement 

 of the author distinctly shows that his Salpingina also embraces common cyclosto- 

 matous species: Alle sind fossil und gehoren dem Jura, der Kreide und der Ter- 

 tiarbildung an«. 



The presence of an operculum in the Salpingina should be a real difference 

 from the Cgclostomaia, but there is no evidence that the author has seen a real 

 operculum in any of the species referred by him to this division. As a species 

 provided with such an operculum he names Escharites fFeliceaJ velata Hag., but this 

 species belongs to quite another division, the Ceidae, which are not provided with an 

 operculum, and what Hagenow has seen is only a closure-plate. 



d'Orbigny ') in 1852 founded a division to which he gives the name Centri- 

 fagines operculines and which he defines as follows: » Cellule centrifuginee toujours 

 pourvue d'un opercule. Colonic tres variable dans sa forme composee de cellules 

 generalement pen saillantes, mais toujours pourvues d'un opercule: partie testacee 

 ou calcaire, s'ouvrant comma une porta pour laisser sortir I'animal*. As to the 

 operculum he later adds: >>D'ailleurs s'il pouvait encore rester quelques doutes a 

 cet egard la presence de ces opercules encore restes en place dans beaucoup d'es- 

 peces fossiles, vient entierement les lever et donner la preuve que cet opercule exi- 

 stait«. To this division d'Orbigny refers two families, the Eleidae and the Myrio- 

 zoumidae, the last of which contains the exstinct genus Foricnla and the recent genus 

 Myriozoum. The last named genus, however, belongs to the Cheilostomata. The above 

 quotation leaves no doubt that d'Orbigny has founded his division Eleidae on the 

 presence of an operculum, and it is a curious fact that all the modern authors with 

 the exception of the present though accepting this division, at the same time deny 

 that its member possesses an operculum, explaining the calcareous plate which may 

 be found closing the aperture of more or less zooecia as a closure-plate. Not a 

 single author even mentions this statement of d'Orbigny. 



Hamm "') in 1881, founded a very artificial division, the S/!(///!fl/o/)or(;!« to which he 

 besides two inoperculate cyclostomatous genera Stiginatopora Hamm {-Hanimia Grey) 

 and Cyrtopora Hag. also referred the operculate genus Melicerilites. He characterizes this 

 division as follows: > Die Zellen sind ahnlich wie die der Tubuliporiden beschaffen. Statt 

 dass sie aber in der mitlleren Axe des Slammes entspringen legen sie sich rings um ein 

 senkrecht stehendes, im Querschnitt rundliches Biindel von langen cylindrischen unter 

 einander parallelen R6hren«. He divides the Stigmatoporina in two groups the second of 

 which (Melicerititesjhe characterizes by the trumpet-shaped distal enlargement of the zo- 

 oecia: ». . zweitens in solche, deren Zellen lang, anfangs sehr dunn sind und erst an der 

 Mundung sich plotzlich trompetenforinig erwaitern«. As we have seen Hagenow has al- 



») 7, p. 605. '-] 8, p. 45, 



