266 
Charakters  umstirzen wird; denn die Fundamente- scheinen mir 
durch die innigsten Beziehungen zur Phylogenese "als sichere er- 
wiesen"; I, on the contrary, take the liberty to express the collegial 
wish that. the considerations and studies contained .in ,this paper 
may help Dr. Schneider to change his view about the systematic 
significance of the colonial characters. — 
"Professor Kristine Bonnevie who has rangeret several 
papers on Norwegian and North-Atlantic Hydroids, among which is the 
report on the Hydroids from the Norwegian North-Atlantic Expedition, 
quite agrees with Schneider in his systematic view, and in the 
last named work. 'says. about the systematic' arrangement proposed 
by the. present author"): "In this family. as in. Campanulinidae 
Levinsen has made a division of genera based upon the nature 
of the; lid of the hydrotheca.. But the remark that. I made 
previously is also. applicable here, namely, that the nature of the 
lid. and of the margin. of the hydrothéeca, are very good specific 
distinguishing features, but that in basing a system upon these 
Characters ;we ascribe ;to them too much importance.” Though the 
author thus acknowledges ; the diversities found in the opercular 
apparatus at least as very good specific characters she does not 
mention' the structure: of the operculum in any of the- species 
named in her work, not éven in the new species described by her. 
". While Bonnevie gives to each species the name of the 
group, to which it is referred, another follower of Schneid er's 
system, Mr. H. B. Torrey”) does not think it necessary, and, 
besides, as: far as I understand him, thinks it an advantage not to 
do: so. - He expresses himself as follows: ,,Anyone who has had 
occasion to work: among the. Sertulariidae will admire the masterly 
way in which Nutting has dealt with the perplexing questions of 
classification. in that family. . I'am not yet prepared, however, to 
abandøn Schneider's plan of segregating the species into typical 
groups which shall tåke thé places of genera, "These ; groups do 
zY 12, p. 48. 
Z) 58, p. 21 
