VAN NAME: COMPOUND ASCIDIANS. 389 
2099 (off Xewfoundland, X. lat. 45° 04', W. long. 55° 23', 72 fathoms, 
August 22, 1886) ; Bay of Fundy; Eastport, Maine (several specimens, 
including the type) ; Casco Bay, Maine; Stations 161 to 164 (off Cape 
Ann, X. lat. 42° 36', W. long. 70° 27', approximately, 54 to 75 fathoms, 
mud and fine sand, August 16, 1878); Station 222 (off Cape Ann, 
X. lat. 42° 33', W. long. 70° 31', approximately, 40 fathoms, fine 
sandy mud, September 21, 1878); Station 184 (off Cape Ann, X. lat. 
42° 30', AV. long. 70° 38', approximately, 45 fathoms, mud, August 29, 
1878); Stations 25 to 31 (Massachusetts Bay, X. lat. 42° 27.5', W. 
long. 70° 36', 48 to 50 fathoms, mud, August 13, 1877) ; Station 349 
(Massachusetts Bay, X. lat. 42° 10.5', W. long. 70° 29', 26 fathoms, 
sand and mud) ; Station 371 (off Chatham, Mass.,' X. lat. 41° 35.5', 
W. long. 69° 35', 34.5 fathoms, coarse speckled sand, September 19, 
1879) ; Station 372 (off Chatham, Mass., X. lat. 41° 40', W. long. 
69° 28.5', 70 fathoms, sand and pebbles, September 19, 1879). 
Genus Lissoclinum Verrill, 1871. 
Verrill's descriptions of this genus and of the species inckided, 
are concerned so largely with external characters and with characters 
common to many or most genera of the family, that we must depend 
on an examination of the type to determine the correct diagnosis of the 
genus. Of the two species, L. aureuni and L. tenerum, the former, 
being the first described (Verrill, 1871a, p. 444) and the only one 
figured, is the type. 
An examination of Verrill's type specimens shows that while 
L. tenerum is a Didemnopsis, L. aureum, the generic type, is closely 
allied to Diplosomoides duhium Hartmeyer, 1903, of the European 
Arctic region. Diplosomoides flavescens Redikorzew, 1907, of the 
Siberian Arctic Ocean, is also closely allied. All these three species 
are distinguished by having the testis consisting of four or more sepa- 
rate or nearly separate radially arranged parts, and by having an atrial 
languet. Diplosomoides Herdman was originally defined as differing 
from Leptoclinum ]Milne-Edwards [= Diplosoma MacDonald] only in 
having calcareous spicules. Leptoclinum [Diplosoma], however, has 
the testis consisting of two distinct somewhat hemispherical parts 
and has no atrial languet. There are species of Diplosombides (D. 
fragile of Bermuda, for instance), which do correspond exactly to 
Leptoclinum, lacking the atrial languet and having a two-parted testis. 
