108 



OHAS. B. WILSON. 



wounds with tlieir powerful jaws. Dr. E. A. Andrews lias 

 suggested to me that possibly the dense coating of slime 

 which is constantly exuded from the JSTemertean's ectoderm 

 may afford it protection. If a minute drop of this slime be 

 placed upon the tongue it will be found so intensely acrid 

 as to parch the whole mouth, and the taste remains for a long 

 time. This quality, then, might effectually prevent the 

 Nereis from inflicting any injury with its jaws. These 

 Annelids do not often leave their burrows altogether, but 

 simply protrude the head and anterior portion of the body in 

 search of prey. Taken in connection with the fact that the 

 Nemertean swallows them tail first, this suggests that they 

 are not ordinarily caught outside their burrows, but that the 

 Nemertean probes around beneath the surface until it strikes 

 the home of an Annelid, and then proceeds to swallow the 

 unfortunate occupant. In such a case the Annelid's jaws 

 would be practically useless, for it could not turn about in its 

 burrow. The snout of the Nemertean, in front of the 

 mouth, is usually turned backward daring the process of 

 swallowing, the proboscis being wholly withdrawn. 



The digestive fluid acts very quickly. Several attempts 

 were made to preserve a specimen with a Nereis nearly 

 swallowed and protruding an inch or two from its mouth. 

 But they failed at first because the Nereis was forcibly 

 ejected as soon as the Nemertean touched the preserving 

 fluid, no matter how far it had been swallowed. A subse- 

 quent attempt was crowned with success ; a Nemertean with 

 an inch of Nereis nearly as large as itself protruding from 

 its mouth was plunged into boiling water for a moment 

 and then preserved in formalin. This produced death so 

 instantaneously that there was no time for ejection, and 

 the perfectly preserved pair still remain to attest the fact 

 (fig- !)• 



But although the first efforts were failures in one direction 

 they were a success in another. The swallowing of an 

 ordinary Nereis occupies about ten minutes, but in every 

 instance it was found more than half digested upon ejection. 



