287 
the Sertulariidae. But Hartlaub 1 ) has also found a blind sack 
in the campanularian genus Silicularia, and I have found it in 
Lictorella pinnata Sars. It is also found in the operculate species 
described as Zygophylax operculata Jåd. (PI. IV, fig. 21) and Zyg . 
grandis V anh. 2 ), and I cannot doubt but that it is also present as well 
in the inopeiculate species related to theru as in the other species 
of the genus Lictorella. The presence of the blind sack in the 
named cases, therefore, seems to be contingent upon the more or 
less pronounced bilateral symmetry. 
v. tampenhausen who also refers Grammaria to the Ser- 
tulariidae says about my reference of Synthecium and the othej’ 
above named forms to the, Lafoeidae 3 ): „Abgesehen aber davon 
dass die erwåhnten Formen so typisch alle iibrigen Sertularien- 
charactere bezitzen ausser diesen einen.und mir.eine 
Trennung nur auf ein Merkmal hin willkurlich vorkommt, scheint 
mir das Vorhandensein oder der Mangel eines Operculums durchaus 
nicht von so einschneidender Bedeutung zu sein.“ As v. Cam- 
penhausen does »ot seem to ascribe systematic significance to 
the arrangement of the hydrothecæ, the typical sertularian characters, 
about which he speaks, must be the bilateral symmetrical structure 
of the hydrothecae, and the more or less extensive connection 
between their adcauline wall and the corresponding axial structures 4 ). 
As to the first named character there is no contrast between the 
named forms and the other Lafoeidae , as most members of this 
family and especially of its freely branched forms show a more or 
less distinet bilateral symmetry, which is found not only in species 
with sessile or adnate hydrothecae, but sometimes also in such 
species the hydrothecæ of which are provided with free stalks. 
*) 19, p. 12, note. 
2 ) 59, p. 815. 
3 ) 14 a, p. 301. 
4 ) Jf v. Campenkausen regards the presence of a well-developed 
diaphragm as a specific sertularian character, I may here point out 
that the diaphragm is quite lacking or imperfectlv developed in ’a 
number of Sertularella- species. 
