DESTEUCTIVENESS OP THE COMMOK DEILL. 697 



and most destructive, as well as most abundant of them all, is the TTrosalpinx cinerea of Stimpson. 

 It is this which is the common "DrUl" of the oyster-beds; and it is its eggs, laid in small vase- 

 shaped capsules, which are often found attached in groups to the under surfaces of stones. 

 Several of the small mollusks mentioned above lay eggs in this way, but the Drill's capsules have 

 very short stalks, or are almost sessile, and are compressed with an ovate outline, while angular 

 ridges pass down their sides. The natural home of the Drill is the tide-pools and weedy borders 

 of rocky shallows, where barnacles, hydroids, anemones, rock-loving limpets, and other associated 

 forms that find shelter among the algae afford it abundant food. Though this is precisely where 

 the Mussels grow till the rocks are almost black with them, it is said that they are never attacked 

 by the Drills. 



The Urosalpinx sometimes strays to the oyster-beds, but is usually carried there with the seed 

 supplies, and, finding plenty of nourishment, lives and increases. Though its multiplication is not 

 very rapid, it is fast enough to make it a very serious obstacle to success in the course of a few 

 years. In nearly every case I was told that formerly there were no Drills, but now the oyster- 

 beds were overrun. This was reported in particular of the Great South Bay of Long Island and 

 at Keyport, 'New Jersey. I heard less of its ravages in New Jersey, except in the Delaware ; but 

 in Chesapeake Bay nearly every dredge-haul in any part of Maryland or Virginia waters brings 

 them up. The Potomac seems to be the district least infested. Of course, in such natural haunts 

 as the rocky shores of Buzzard's Bay and Connecticut they would be present if there were no 

 Oysters, and are all the harder to dislodge. 



Once having attacked an oyster-bed, they work with rapidity, and seem to make sudden and 

 combined attacks at considerable intervals. Their disappearance from certain restricted localities, 

 too, for a long time is unexplained. 



What is the best way to combat them, or whether there is any hope of ridding the beds of 

 them, are questions often discussed by oyster-culturists. It is certain that a great deal of trouble 

 might be avoided if care were exercised in culling seed to throw out — not into the water, but on 

 the ground or deck — all the Drills, instead of carrying them to one's beds, deliberately planting 

 them, and then grumbling at destruction which previous care would have avoided. It would cost 

 less in point of mere labor, no doubt, to prevent this plague than to cure it when it became no longer 

 endurable. Some planters clean up pieces of bottom very thoroughly before planting, in order to 

 get all this sort of vermin out of their way, as well as to stir up the mud and fit it for the reception 

 of spat. It is on hard bottom that Drills are especially troublesome, and here some planters go 

 over the ground with a fine-meshed dredge in order to get them up, but they fail to catch all. 

 This is done at Norwalk, Connecticut, I know, and the men who have steamers find in the celerity 

 with which they are able to accomplish this sort of work a great argument against any restriction 

 to exclusively sailing-rig. 



The Drill can be exterminated to a great extent, also, by diligently destroying its eggs. Small 

 boys might well be paid to search for them and destroy them among the weedy rocks by the shore 

 at low tide. A gentleman at Sayville, Long Island, assured me that in those years when eels 

 were plentiful the Drills were kept down because the eels fed on their eggs. This gentleman said 

 in the Great South Bay the Drills were nearly conquering the planters, and he advised the 

 removal of all shells from the bottom of the bay, in order that the Drills might have nothing left 

 on which to place their eggs. This might do there, where there are no rocks along the shore and 

 the Drill is not native; but I doubt whether so sweeping a measure of protection could ever be 

 carried out. 



On the Pacific coast Qastrochtena and various pholadiform mollusks are a great bane to the 



