1879.] BA [Fewkes. 
This rudimentary tube runs directly under the ridge which seems to 
me the same as that which has the letter (c) in Leuckart’s figure, PI. 
il, fig. 6, Zool. Untersuch. The secondary tube, which originates 
from an enlargement where the right hand tube, looking at the lower 
surface of the bell as it swims in the water, joins the circular vessel, 
and which ends in the digitate portion described, may also be related 
to this rudimentary tube. ; 
As the nectocalyces of all Physophoridae, exclusive of course of 
Athorybia, Physalia and Rhizophysa, where they do not exist, have 
bilateral symmetry as referred to a plane, passing through ventral 
and dorsal line as defined by Claus and Haeckel,! and as the same 
occurs also in Gleba (Hippopodius), and the second nectocalyx of 
Epibulia (Galeolaria), we have an anterior and posterior or superior 
and inferior spheromere as well as a right and left. ‘These sphero- 
meres resemble each other, and in most Siphonophores have the chym- 
iferous tubes passing directly to the circular vessel, while the lateral 
spheromeres have tubes which do not pass so directly, but make a 
curious turn. dAbyla pentagona does not present in its larger necto- 
calyx a bilateral symmetry of this kind in its chymiferous tubes. One 
side of the larger bell, however, is different from the other, in that it 
has the longitudinal canal (Lingskanal), covered by a plate into 
which the stem is withdrawn on one side which is wanting on the 
other. I propose to call that the inferior side of the large necto- 
calyx. If the float is made out to indicate the anterior end of a 
Siphonophore in the Physophoridae, as to my knowledge it never 
has been, and if (as I believe), Leuckart? is right in consider- 
ing that the somatocyst (“‘Saftbehilter,’”’ ““Athemhohle,”) of a Calyco- 
phore is homologus to one of those little blind tubes (‘‘ Mantelge- 
fass,”) on the median tube of the nectocalyx of an Agalma, these two 
sides of the larger nectocalyx of Abyla may be called anterior and 
posterior. Whether we use the terms anterior or superior all depends 
upon whether the float indicates the anterior extremity of the stem 
from which it buds or the superior end of the same, together witha 
true homology of the regions of the nectocalyx of a Calycophore. The 
1 Leuckart led the way to the institution of the term ventral line when he showed 
that the appendages all arise from one side of or in a direct line on the stem. 
Leuckart. Zool. Untersuch, p. 14. Archiv fiir Naturg., 1854.—Claus., Zeitschr. fiir 
wiss. Zool. x11, 7, 27.—Haeckel. Zur Entwick. der Siphon., p. 12.—Claus, Halis- 
temma tegestinum, p. 5. 
2 Leuckart. Zoologische Untersuchungen, p. 10. 
PROCEEDINGS B.S. N. H.— VOL. XX. 21 MARCH, 1880. 
