On an Australian Land Nemertine. 89 



Willeinoes-Sulim appears to regard* this as a normal mode 

 of locomotion. From my own observations I am inclined to 

 regard it as accidental, and I think that the proboscis is 

 normally used only as a weapon of offence or defence, 

 probably for catching insects, but this I have not observed. 

 As already stated, when the animal is crawling under 

 ordinary circumstances the proboscis is entirely withdrawn 

 into the body. 



So much for the external characters of the living animal. 

 Before passing on to describe the minute anatomy it may be 

 as well to say a few words as to the methods of killing ami 

 preserving specimens. Unfortunatel}" the animal is so large 

 and opa(|ue that it is difficult to study the internal anatomy 

 satisfactorily in the living worm, and, owing to the extreme 

 irritability of the proboscis and the delicacy of the whole 

 organism, it is an unusually difficult matter to kill and 

 preserve the animal in a satisfactory condition, foi' the 

 violent movements of the proboscis are v^ry apt to cause the 

 body to break up. 



The following are the results of a number of experiments 

 which I made with a view to finding the best method of 

 killing and preserving specimens : — 



(a.) By suddenly immersing the living worm in strong 

 methylated spirits. This is sometimes successful, but the 

 proboscis is always more or less everted in the spirit and 

 frequently the boclj'' breaks uj). 



Q).) By suddenly immersing in very dilute aqueous osmic 

 acid. Only one specimen was tried ; the proboscis was 

 everted and the body broke up badly. 



(c.) By suddeidy immersing in a cold saturated alcoholic 

 solution of corrosive sublimate. This is fairly succes.sfnl but 

 the proboscis is always everted and sometimes the body 

 breaks. 



(d) By pouring a hot aqueous solution of corrosive 

 sublimate on the living worm. Tliis kills the animal 

 nearly instantaneously, with the body generally intact but 

 the proboscis everted. The heat employed, however, can 

 scarcely fail to injure the histology of so delicate an 

 organism. 



(6.) By lirst holding the worm in the vapour of chloroform 

 for about half a minrr^te. Hold the worm on a lifter or glass 



* " On a Land-Nemertean found in the Bermudas," Annals and Ma/j<izine 

 of Natural History, Series 4, Vol. XIII, 1874, p. 409. 



