BIOLOGICAL STUDY OF CHESAPEAKE BAY WATERS 
329 
genus, Cyttaroeylis, belonging to the Tintinnidae has been studied sufficiently to 
make it possible to draw any conclusions as to distribution. Specimens were found 
on every cruise during the year 1916 (January, March, April, June, July, and Sep- 
tember). The highest counts were obtained from samples taken during the March 
cruise, and the numbers were more abundant in the samples from the lower part of 
the bay. 
COELENTERATA 
PORIFERA 
Practically all of the collecting done on the survey was in the offshore waters, 
so that the sponges of the shallower water have not been investigated. Dredging 
with the beam trawl and with the mud bag at the shallow stations have brought to 
light, however, four species of sponges, one of which is new, and a new variety. These 
have been identified by H. V. Wilson, and I am indebted to him for the following list: 
Tetilla laminaris George and Wilson, T. laminaris var. symmetrica n. var., Suberites 
paradoxus Wilson, Halichondria panicea Johnston, and Microciona prolifera Verrill. 
Tetilla laminaris was dredged on one occasion only at 10 meters at area K. This 
area is located on the eastern side of the bay opposite the mouth of the Potomac 
River. The specimen was taken during July, 1920, in water of 14.79 per mille salinity 
and 24.4° C. temperature. The bottom in this region was partly sandy and partly 
muddy (depth 10 meters). T. laminaris George and Wilson, var. symmetrica was 
found growing at area D, off New Point Comfort (depth of 8 meters) on a sandy 
bottom. Three specimens were brought up during the April, 1920, cruise from 
water of 21.23 per mille salinity and 11.1° C. temperature. A new species, Suberites 
paradoxus was dredged during the July, 1920, cruise at area C, off New Point Comfort 
(depth about 13 meters). The bottom in this region was variable in character, and 
the temperature and salinity of the water from which the specimen was taken were 
22.0° C. and 22.49 per mille. During the January, 1921, cruise numerous fragments 
of Halichondria panicea were found at area Q (depth about 14 meters) off Sandy 
Point and at area A (depth about 46 meters) near Cape Charles City. In the first 
case they were taken from water of 21.59 per mille salinity and 4.2° C. temperature, 
while in the second case the salinity and temperature were about 26.00 per mille 
and 4.9° C. Microciona prolifera was dredged during the July, 1920, cruise at area 
P (depth about 13 meters) off Point No Point and area I (depth about 13 meters) 
just south of the Maryland and Virginia line. The salinities were 17.27 per mille 
and 15.47 per mille, the temperatures 23.5° C. and 25.2° C., respectively. 
Undoubtedly the ideal home for sponges is in a region where there are plenty of 
solid objects for attachment, so one finds them living well among rocks, stones, shells, 
corals, etc. They are known not to do so well in regions where the bottom is made 
of soft mud or fine sand. For example, in the deeper part of the fjords (Appellof, 
1912) of Norway, where the bottom is muddy, the sponges are absent. It is not 
surprising, then, that many specimens or species of sponges were not found during 
the offshore dredging in Chesapeake Bay, since much of the bottom in the deeper 
parts of the bay is muddy. It is of interest to note that all of the specimens collected, 
with the exception of one, were taken from regions where the depth ranged from 8 
to about 14 meters — in other words from the shallower areas of the bay. No sponges 
were dredged from the mouth of the bay, which is largely a region of shifting sand. 
All the specimens found come from the lower half of the bay, below area P, near the 
mouth of the Potomac River, and none were taken in water of a lower salinity than 
14.79 per mille. 
