172 ME. A. W. WATERS ON 



the tubules by tbe side of the zooecia opening near the zooecial 

 aperture, as figured by Smitt (" Krit. Fort." 1866, pi. 8. fig. 11). 

 Not having seen any ovicell, or made any measurements of this 

 specimen, it is better not to definitely decide that it is identical 

 with our Arctic variety, although I am aware of no difference. 

 The specimen is discoid. JBerenicea prominens, Lamx., is not 

 figured or described by Lamouroux or d'Orbiguy as having 

 tubules, but in the Paris Museum d'Orbigny's tube 13770 

 contains Diastopora obelia with tubules and another species 

 without, all labelled B. prominens. 



Berenicea prominens, Lamx., is G-regory's type of Berenicea, 

 but Berenicea we can only consider as Diastopora ; and whether 

 it is the D. ohelia, Johnst., as stated by Gregory, or another 

 Diastopora can never be decided by the description or figures, 

 as these would do equally well for most Diastopora and for 

 species in other genera as well. Norman * considers that 

 Berenicea prominens, Lamx., is Chorizopora Brongniarti, Aud., 

 and certainly Lamouroux's figure could not settle the question 

 as to whether Diastopora was intended ; but when we examine 

 the other two figures of " Berenicea " we can hardly doubt that 

 they are Diastopora. "We thus have two authorities wishing to 

 overthrow two well-recognized genera, Diastopora and Chorizo- 

 pora, one believing that Berenicea prominens, Lamx., was 

 Diastopora ohelia, while the other thinks it was Chorizopora 

 Brongniarti, Aud. 



Canon Norman is perhaps better acquainted with the older 

 literature of the Bryozoa than anyone else, he is a most careful 

 observer, and is l^nowu to possess a splendid collection for 

 reference, and therefore we may say that he has given us a most 

 instructive example of the difficulty of trying to make out what 

 the older authors described. We all have to spend too much 

 time in looking back, to find out what was meant when species 

 were described without any of the characters which are now 

 recognized as of greatest importance being used. We should 

 all be better employed in going forwards. 



For the species of Diastopora with adventitious tubules it may 

 possibly be advisable ultimately to accept a new genus, but the 

 name Diplopora f proposed by Jullien & Calvet has already been 



* " Natural History of East Finmark," Ann. Mag. Nat. Hist. ser. 7, vol. xi. 

 p. 569, 1903. 



t " Bryozoaires provenant des campagnes de I'Hirondelle," Monaco, 1903, 

 p. 115. 



