VAX NAME: SIMPLE ASCIDIANS. 563 
Margin of anus with numerous lobes. A slight rudiment of a pyloric 
caecum is present. 
Gonads one on each side, each consisting of an elongated, very 
sinuously curved o^'ary, and a number of small male glands gathered 
into more or less compact groups along one or both sides of the ovary 
(especially along its ventral side). The general direction of the 
ovaries is horizontal with the open end bent up toward the atrial orifice; 
that of the right side bends very abruptly, often doubling forward 
almost parallel to the main portion for a little distance (see PI. 58, 
fig. 88). The ducts from the groups of testes run to and follow the 
ovary, uniting to a common duct ending in the usual way beside the 
oviduct. 
With this British species, originally described by Alder and Han- 
cock in 1848, and well figured in their later work (1905-1907), the 
writer identifies Packard's Cynthia placenta (1867) from Labrador. 
Packard states it is also common in the Bay of Fundy. Verrill 
(1871a, p. 94) states that he examined Packard's specimens and 
found among them one of a different (papillose and sand-covered) 
species. This, however, is immaterial to the discussion of the present 
species. The important fact is that it shows that Verrill had an 
opportunity to compare and determine the identity of his Eastport 
specimens with Packard's types. One of Packard's types is figured 
by Binney (1870, pi. 2.3, fig. 322). Verrill, however, did not employ 
Packard's name placenta, for he believed incorrectly that Ascidia 
carnea Agassiz (1850) was the young of this species, hence he employed 
the name carnea, and his statements in his several papers refer partly 
to Agassiz's and partly to Packard's species. Subsequently he con- 
cluded that Agassiz's species was identical with the Ascidia tuherculum 
of Fabricius (1780) and he then adopted the latter specific name in 
place of carnea. Fabricius' species is, however, probably Dcndrodoa 
aggregata (Rathke) according to Hartmeyer (1903, 1909), and, if 
so, has nothing to do with Packard's placenta or Agassiz's carnea. 
Alder and Hancock (1905-1907) record T. coriaceum from North- 
umberland, the Dogger Bank, Falmouth, and Shetland. It is said 
to inhabit "deep water, usually on shells." Dr. Hartmeyer has 
recently informed the writer that he believes Tethyum loveni (Sars), 
1851, to be also identical with the species, a conclusion with which 
the writer agrees after examining a specimen of T. loveni kindly sent 
by Dr. Hartmeyer. The species is therefore widely distributed in the 
northern regions, Tethyum loveni having been recorded from Spitz- 
