314 PROFESSOR W. A. HERDMAN ON THE 
that Synstyela, Giard, has the prior claim and must be retained as the name of the 
genus, even when, as happens to be the case, our knowledge of the internal characters 
has been increased and the definition added to since the genus was originally created. 
Consequently I must regard Micuagnsen’s Allwocarpa zschaui as a Synstyela, and 
furthermore I find myself unable to distinguish it as a species from S. imerustans of 
the Challenger Report. In Micuaxtsen’s “ Revision der compositen Styeliden oder 
Polyzoinen,” * where both species are described, in his table on p. 73 he distinguishes 
them by the proportions of the oviduct and the number of internal longitudinal bars in 
the branchial sac, as follows :— 
S. zschaw having the oviduct broader than long, and having sixteen to seventeen 
bars on each side; and 
S. incrustans having the oviduct longer than broad, and having twelve to fourteen 
bars on each side of the sac. 
Now, in the first place, with a soft, easily deformed structure like the oviduct it is 
almost impossible to be sure of the true proportions ; and secondly, I find them varying 
considerably in my specimens; so that I cannot say they agree more in this character — 
with the one species than with the other. Then as to the number of longitudinal bars, — 
on dissecting out and mounting a branchial sac from a Scotea specimen I find the 
number of bars to be fifteen on each side. According to Micuax.seEn, if it had sixteen 
the species would be zschauwi, and if it had fourteen it would be incrustans. Under 
these circumstances, and as I find the specimens before me agree equally well with the 
descriptions of these two species, | think there can be little doubt but that A. zschaw, 
Michaelsen, is a synonym of Synstyela icrustans, Herdman. 
Diandrocarpa monocarpa (Sluiter) is certainly not the same species as Synstyela 
incrustans, although it is probably a Synstyela. The number of longitudinal bars in 
the branchial sac is very much smaller than in the present species. 
Family Ascrprp&. 
Ascidia charcoti, Sluiter. 
Locality.—Station 325, in shore pool, Scotia Bay, South Orkneys, February 2, 
1904. | 
The single large Asczdia in the collection clearly belongs to Sturrer’s A. charcoti, 
a species found by the Charcot Expedition to be abundant at “Ile Booth Wandel.” 
The Scotia specimen measures 8°5 x 5°5 x 2 cm., and was attached by a small area in 
the middle of the left side. The branchial aperture has only seven lobes, a curious little 
detail in which it agrees with Suurrer’s description. The atrial has the usual six lobes 
characteristic of the genus. The test reaches a thickness of 2 to 3 mm., but has not 
the red colour mentioned by Siurrer; and the mantle is unusually thick and spongy 
* Mitteilungen aus dem Naturhistor. Musewm, xxi,, Hamburg, 1904. 4 
