NATURAL HISTORY OF SELBORNE. 67 



cancer-doctress, finds it expedient to amuse the country with this 

 dark and mysterious relation. 



The water-eft has not, that I can discern, the least appearance 

 of any gills ; for want of which it is continually rising to the sur- 

 face of the water to take in fresh air. I opened a big-bellied one 

 indeed, and found it full of spawn. Not that this circumstance 

 at all invalidates the assertion that they are larva; for the larvce 

 of insects are full of eggs, which they exclude the instant they 

 enter their last state. The water-eft is continually climbing over 

 the brims of the vessel, within which we keep it in water, and 

 wandering away ; and people every summer see numbers crawling 

 out of the pools where they are hatched up the dry banks. There 

 are varieties of them, differing in colour ; and some have fins up 

 their tail and back, and some have not. 



NOTE TO LETTER XVIII. 



1 The Gasterosteus pungitius is the ten-spined stickleback. The other is the 

 common one with three spines. 



LETTER XIX. 



SELBORNE, August i7//z, 1768. 



DEAR SIR, I have now, past dispute, made out three distinct 

 species of the willow-wrens (motatilla trochilt) which constantly 

 and invariably use distinct notes. But at the same time I am 

 obliged to confess that I know nothing of your willow-lark. In 

 my letter of April i8th, I had told you peremptorily that I knew 

 your willow-lark, but had not seen it then ; but when I came 

 to procure it, it proved in all respects a very motadlla trochilus, 

 only that it is a size larger than the two other, and the yellow- 

 green of the whole upper part of the body is more vivid, and the 

 belly of a clearer white. I have specimens of the three sorts now 

 lying before me, and can discern that there are three gradations 

 of t sizes, and that the least has black legs, and the >ther two flesh- 



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