14 
calycles on a short, wrinkled pedicel. On the other hånd Le vi nsen 
finds a great likeness between such forms as Lafoea dumosa and 
Cuspidella humilis and costata, and between Grammaria (Filellum) 
serpens and Cuspidella procumbens; it seems to me to be very 
doubtful, whether these similarities are really owing to a genetic 
relationship between the forms in question; such characters as 
free or adnate hydrothecæ are probably due to the influence of 
outer circumstances and have only a systematic value within narrow 
limits. Le vi nsen points out that “the long siender, sometimes 
tubuliform hydrothecae of the genus Stegopoma leave no doubt as 
to the near connection of the latter genus with the Lafoeidae." 
It is true, that some resemblances exist between Stegopoma and 
Lafoea , and I shall not deny any possibility of a relationship, but 
it is not beyond question. The hydrothecæ of Stegopoma, Cuspidella 
and Lafoeina seem to me to indicate a comparatively low systematic 
position, and it seems to me rather premature to establish at present 
a relationship as a secured faet. — I am more inelined to think, 
that the nearest relatives of the Lafoeidæ are to be searched for 
within the other main-group of u Campanuli?iidæ": Calycella, Tetra- 
poma and Thyroscyphus , partly on account of the above mentioned 
likeness between the two first mentioned genera and the small 
species of Lafoea, partly because Thyroscyphus as well as Abieti- 
nella (which as mentioned above is closely related to certain La¬ 
foeidæ) seem to indicate a transition to the Sertularidæ. 
Thus I am inelined to establish the following families: 
Cuspidellidæ, including a number of low genera provided with 
an operculum originating from the uppermost part of the sidewall 
of the hydrothecæ. 
Lafoeidæ, including mostly inoperculate forms, but moreover a 
few genera provided with a simple operculum; as a rule aggregated 
gonosomes. 
Calycellidæ, with a polvsymmetrical operculum, originating 
from the original roof of the hydrotheca. 
Sertularidæ , including operculate forms with bilaterally syraine- 
