VAN NAME: COMPOUND ASCIDIANS. 395 
long. 70° 28.5', approxinuitely, (JO fathoms, mud); Massachusetts 
Bay, near Stelhvagen's Bank, DO fathoms; Station 264 (off Cape Cod, 
Race Point Light, S. G5° \\., 15 miles, X. lat. 42° 10', \V. long. 69° 
56.5', 80 fathoms, blue mud, July 28, 1879); Station 873 (off Martha's 
Vineyard, Mass., X. lat. 40° 02', W. long. 70° 57', 100 fathoms, soft 
sticky mud, September 13, 1880). 
The specimens with abundant spicules are not numerous, and are 
from the vicinity of Eastport, ]Maine, except one from Station 2455 
(off Xewfoundland, X. lat. 47° 21', W. long. 51° 38' 30", 81 fathoms, 
brown sand, June 26, 1885), and one from Station 78 B (near Jeffrey's 
Ledge, X. lat. 43° 04', W. long. 70° 30', 35 fathoms, September 13, 
1873). 
Family SYNOICIDAE Hartmeyer, 190S [= POLYCLINIDAE Verrill, 
1871]. 
Genus MacrocliiNUM Verrill, 1,871. 
Colony massive, usually rounded and attached by a narrow base. 
Systems small and simple, circular or elliptical, wanting or indis- 
tinguishable in some stages of growth of the colony. 
Zooids elongated. Post-abdomen sessile and very long when fully 
developed. Branchial aperture six-lobed; atrial aperture more or 
less produced into a tubular or funnel-like form and provided with a 
three-parted languet. Intestinal loop twisted in some individuals, 
but not in others. Stomach wall smooth or occasionally with distinct 
but small and shallow areolations. 
Of the European writers who have described the following species 
(with which, as shown by Bjerkan (1905, pp. 17, 18), Verrill's M. 
crater is identical), Alder (1863) and Bjerkan (1908) alone seem to 
have noted the areolation of the stomach. The latter author suggests 
that this indicates a relationship to Synoicum Phipps. This is a con- 
clusion at which the writer had already arrived before seeing Bjerkan's 
article. Xot only the areolation of the stomach, but the somewhat 
produced atrial siphon bearing the three-fingered languet and the small 
circular systems indicate a relationship to the latter genus, but the 
writer has not had the opportunity of studying any species of Synoicum 
and cannot express any opinion as to whether the relationship with 
that genus is sufficiently close to make uniting the two genera advisable. 
