
1890.] A Zoological Reconnoissance. 437 
instead of being borne on simple or branched pedicles, as in the 
Tubularidz, are produced on distinct coryniform zooids—small, 
rudimentary polypites, which are homologous with the so-called 
gonoblastidia of Hydractinia or Dicoryne. It is, as I have said 
before, a cluster of polypites nearly related to Coryne; but its 
marked peculiarities would seem to entitle it to stand as the type 
of a special family.” 
The author would here offer the following generalization to 
which he has been led by the consideration of two facts exhibit- 
ed in the characters of the animal above described. First, the 
basal cirri of the first stage are homologous to the lower or ex- 
terior tentacula of Tubularia. Secondly, these cirri, or tentacula, 
are lost ” with the growth of the animal, and do not appear in 
the second stage. Hence we should consider the Tubularide, 
in which they are persistent, as lower in the scale. It might add 
some weight to this conclusion to call attention to the fact that 
the meduse of Tubularia assume the form of Actinulz, in which 
we have a remote resemblance to the young Acaulis. 
It may be deduced, also, from the above account that the 
species just described, having basal tentacula, is more embryonic 
than Coryne and its allies, in which they never appear, so that 
it is correctly classed between that genus and Tubularia ; and if, 
as is possible, the single circle of tentacula in the Sertularide is 
homologous with the basal tentacula of Acaulis and Tubularia, 
it would follow that that family should stand lower in an ascend- 
ing scale of classification. The disappearance of the verticil of 
filiform tentacles in Acaulis is certainly not an objection to con- 
sidering this genus as allied to Myriothela, especially since the 
account which Allman gives of the embryology of Myriothela, 
published subsequently to Hincks’s “ History of British Hydroids,” 
shows that Myriothela has these or similar tentacles." 
10 In regard to Hincks’ dissent from Prof. Allman’s opinion in regard to the affinities 
of Myriothela, and the grounds of his objection, it is only necessary to refer to Allman’s 
a type pr, a special family.” 

1 Probably absorbed, not deciduous. 
