BIOLOGICAL STUDY OF CHESAPEAKE BAY WATERS 
339 
were taken at station 8832 and one at station 8834. While the use of a nonclosing 
bottom net and the limited number of samples makes it impossible to draw any con- 
clusions of unquestionable trustworthiness concerning the precise vertical distribu- 
tion of S. elegans and S. serratodentata, the indications are that during the August 
cruise the latter species was more abundant in the deeper layers, since practically no 
specimens (only 3 specimens at station 8834 and 1 at station 8837) were found in the 
surface hauls. The gradually decreasing numbers of specimens of S. serratodentata 
from the 100-fathom line to the mouth of Chesapeake Bay, as seen in surface and 
bottom towings, and the practical absence of this species in the bay throughout our 
cruises are in keeping with Bigelow’s (1922, p. 153) statement that it is the “more 
oceanic” of the two species under consideration. 
BRYOZOA 
The offshore waters of Chesapeake Bay have yielded 17 species of Bryozoa. 
These have been identified by R. C. Osburn. He calls attention to the fact that the 
number is small for such a large area, but it should be mentioned that the survey 
covered only the deeper waters and that no special efforts were made to investigate 
one region more than another in order to find a larger number of species of this group. 
The list of species follows: Barentsis discreta (Busk), Grisia eburnea (Linnaeus), 
Bugula gracilis var. uncinata Hincks, Bugula turrita (Desor), Electra pilosa (Linnaeus), 
Membra nipora membmnacea (Linnaeus), Hemiseptella denticulata (Busk), Hippothoa 
hyalina (Linnaeus), Schi:opodrella unicornis (Johnston), Microporella ciliata (Pallas), 
Alcyonidium verrilli Osburn, Alcyonidium parasiticum (Fleming), Anguinella palmata 
Van Beneden, Bowerbankia gracilis var. caudata (Hincks), fAmathia alternata Lamou- 
roux, fVictorella pavida Saville Kent, and Triticella elongata (Osburn). 
Most of the specimens collected were taken from the shallower areas of the 
offshore waters. Only a few specimens came from the deep holes such as areas A, J, 
R, and S. Amathia alternata which Osburn found in abundance on the beach at 
Beaufort, N. C., was dredged from area G in the mouth of the bay; area G' , nearby, 
off Old Point Comfort; and areas A, B, and C, which mark a line across the bay 
from Cape Charles City to New Point Comfort. Its distribution in Chesapeake 
Bay seems to be limited to the extreme lower end of the bay, as has been pointed out 
by Osburn, and it was found only in water of a bottom salinity ranging from about 
22 to 31 per mille. 
Eight other species, Barentsia discreta at area A (23.96 per mille), Bugula gracilis 
var. uncinata at area A (27.06 per mille), Electra pilosa at area F (31.08 per mille), 
Hippothoa hyalina at area E, Schizopodrella unicornis at area B (24.33 per mill e), 
Microporella ciliata at area E, Alcyonidium parasiticum at area F (31.08 per mille), 
and Bugula turrita at area E were taken only once and at the areas mentioned. While 
ail of these localities are at the extreme lower end of the bay, the number of specimens 
collected is so small that little should be said of the distribution. 
One of the most abundant bryozoans found in the bay was the large, fleshy 
Alcyonidium verrilli, which has been recorded before only from southern New Eng- 
land and New Jersey. Osburn has stated that it was found at areas all over the 
southern half of the Chesapeake Bay but no farther north than at area L, which is 
close to the mouth of the Potomac River. Its frequent capture in the region men- 
tioned during all cruises and the entire lack of specimens from area L to area U, near 
Baltimore, during the same cruises constitute convincing evidence that its distribu- 
19SS— 30 5 
