360 
BULLETIN OF THE BUREAU OF FISHERIES 
Callinectes was made by us with the beam trawl. This occurred at area G', off 
Old Point Comfort, where the depth measures about 28 meters. It was during 
the December, 1920, cruise that the specimens were caught when the bottom water 
temperature was 10.1° C. The collection consisted of 32 female and 15 male speci- 
mens, mostly of large size. All of them were inactive, owing, no doubt, to the low 
temperature of the water (Churchill, 1919). In the same haul of the beam trawl, 
which as usual lasted for 10 minutes, 11 flounders and 26 croakers were captured. 
Since Callinectes is known to occur all over the bay and even well up into the 
rivers, it must be capable of living in waters of a great range of salinities. 
The “mud crab ” Neopanope texana sayi (Smith) has been taken in larger numbers 
on our cruises than any crab found in the bay, but none have been collected north 
of the mouth of the Potomac River. The specimens of this species which have 
been deposited in the United States National Museum by other collectors came 
from the lower bay, judging from the data where the localities are known definitely. 
Our specimens have been found at areas A, B, C, D, F, G, G', I, J, K, 0 , and Q. 
No specimens have been reported from the Potomac River, even at area M, N, and 
N' in its mouth. The records of others show that this species is distributed from 
Provincetown, Mass., southward and that it frequents muddy bottoms in bays 
and sounds. The character of the bottom, the large numbers of specimens collected, 
the occurence of ovigerous females and juvenile forms indicate that Chesapeake 
Bay is an ideal locality for this mud crab. 
Specimens have been found at all seasons of the year and during the July, 1920, 
cruise ovigerous females have been captured. Undoubtedly summer is the breeding 
season. During the cruises of the fall, winter, and spring, juveniles, probably develop- 
ing from eggs of the previous summer, have been collected; but on the summer 
cruises according to our records they have not been found. 
The salinity and temperature records show that for 26 hauls the bottom salinity 
ranged from 14.79 to 31.62 per mille and the bottom temperature from 4.2° C. to 
25.2° C. 
Rithropanopeus harrisii (Gould), which may be included under the “mud crabs” 
and which was formerly classed under the genus Panopeus, was caught but once dur- 
ing the survey’s cruises — namely, at the mouth of the Eastern Bay, where the depth 
was 37 meters and the bottom was soft, black mud. Undoubtedly, the occurrence 
under such conditions was unusual. It has been collected frequently along the shores 
of Chesapeake Bay, both in the upper and lower regions, and often in creeks and 
rivers. Rathbun (1905) reports it from near the high-water mark under stones and 
Gould (Rathbun, 1905), has found it in Cambridge marshes and c lin ging to floating 
seaweed in the Charles River. The most abundant catches from Chesapeake Bay 
deposited in the United States National Museum have come from tributary creeks 
and rivers. 
Specimens have been collected during all seasons of the year. Ovigerous ones 
have been found in June and September and juvenile forms in June, July, August, 
and September. 
JLurypanopeus depressus (Smith), another “mud crab,” apparently lives out 
farther from the shore, for it was taken in regions where the depth of water ranged 
from 11 to 48 meters. Specimens were captured at areas K, P, and I. Others were 
found near area R and off the mouth of the Potomac River. Females bearing eggs 
were captured in April and juvenile forms in April, October, and December, 
