468 KEPORT OI^OMMISSIONER OF FISH AND FISHERIES. 



and G. imgnax occur together. This was found by Mr. Prudden to be 

 the case, both on the marshes bordering West Eiver and on those of 

 Mill Eiver near ^evf Haven. They are abundant along both these 

 streams. The holes made by this ^ecies are much larger than those of 

 O. 2)2(f/nax. Some of them are an inch and a half to two inches in 

 diameter. 



The "blue crab'' or common edible crab, Callinectes hastatiis, (p. 367,) 

 frequents the brackish streams and estuaries, where it is often taken in 

 large quantities for the markets. These are usually brought to market 

 early in May, but the "soft-shelled" ones, which are more highly es- 

 teemed, are taken later. These soft-shelled individuals are merely those 

 that have recently shed their old shells, while the new shell has not had 

 time to harden. The period of shedding seems to be irregular and long 

 continued, for soft-shelled crabs are taken nearly all summer. The young 

 and half-grown specimens of this crab may often be found in consider- 

 able numbers hiding in the holes and hollows beneath the banks during 

 the flood-tide. Wheu disturbed, they swim away quietly into deeper 

 water. These small crabs are devoured by many of the larger fishes. 

 During flood-tide the large crabs swim up the streams like many fishes, 

 and retreat agaiu with the ebb. They feed largely on fishes, and often 

 do much damage by eating fishes caught in set-nets, frequently making- 

 large holes in the nets at the same time. 



The "mud-crabs," Panopeus Sayi (p. 312) and P. depressus, (Plate I, 

 fig. 3,) are very common in all the muddy estuaries and harbors. P. 

 Harrisii also occurs in similar -places ; it is far less common, and appar- 

 ently usually lives higher up toward high-water mark, under stones, &c., 

 but it has been found on the salt-marshes at the mouth of Charles Eiver, 

 according to Dr. A. A. Gould. 



The Orcliestia palustris Smith, is found on the salt-marshes, where it 

 occurs under drift-wood, vegetable debris, &c., extendhig its range 

 nearly or quite up to fresh water, and at times living in places that are 

 almost dry, above high-water mark. 



The Squilla empusa (p. 369) burrows in muddy shores and bottoms at 

 or below low-water mark. 



The Gehla affinis (p. 368, Plate II, fig. 7) also lives in similar places in 

 deep burrows, as described on a previous page. 



The " horseshoe-crab," Limnlus Folypliemus (p. 340,) is also a com- 

 mon inhabitant of muddy bottoms, in estuaries, where it grows to great 

 size. 



The most common Annelids are partly the same as those given 

 above for the sandy shores. The Nereis virens is generally very abun- 

 dant; the two species of Rhynclwhohis are common; and also Lumhri- 

 conereis opalina, (Plate XIII, figs. 69, 70;) Cirratulus grandls, (Plate XY, 

 figs. 80, 81 ;) Polycirrus eximiiis, (p. 320, Plate XYI, fig. 85 ;) Chwto- 

 branchiis sanguineus, (p. 320;) and several other less conspicuous species. 



Among the Gastropods by far the most abundant species is the llya- 



