NOTES ON OLIGOCHATES. 65 
From this table it will be seen that we have at least four 
distinct endoplastic products and perhaps three distinct 
chemical substances in the ccelomic corpuscles of Vermiculus 
and Enchytrzeus, which are probably of an albuminoid nature.! 
That none of the products are mucin is proved by their 
solubility in acetic acid ; that none of them are chitin is proved 
by the first three being soluble in caustic potash and the 
fourth in acetic acid. That they are neither of a fatty nor of 
an amyloid nature is shown by the action of ether, osmic acid, 
and iodine (which does not stain them dark). 
Notes on the Cuticle and Chete of Oligochetes. 
It has long been known that the cuticle of the Oligocheta is 
not made of chitin (Timm, 12; LHisig, 6), since it is readily 
soluble in caustic potash; but few, if any, observations seem 
to have been made with a view to acquiring a more definite 
knowledge of the character of the substance of which it is 
formed. Below are given the results of some experiments 
performed on the cuticle of the common earthworm, Lum- 
bricus herculeus. The worms were killed in 30 per cent. 
alcohol, and placed for a time in water until the cuticle could 
be easily peeled off. The cuticle, having been thoroughly 
washed in salt solution and distilled water, was then experi- 
mented upon in test-tubes. It is insoluble in alcohol and 
ether; soluble in hot distilled water (before boiling-point is 
reached), in solutions of ammonia or weak potash, in lime 
water, in weak mineral acids, in oxalic acid, and with some 
difficulty in acetic acid.” Cuticle dissolved in distilled water, 
boiled and filtered, gives a slightly viscid solution of whitish 
opalescent colour, which does not thicken on cooling. On 
1 In a recent paper on “The Process of Secretion in the Skin of the 
Common Eel,” Professor E. Waymouth Reid comes to the conclusion that 
the thread-like secrections from the epidermis are formed of an albuminoid 
possibly allied to keratin (‘ Phil. Trans.,’ v., 185, B. 1894). The substance 
presents no great resemblance to that found in Enchytreus. 
2 The same results were obtained with the cuticle of Vermiculus and 
Enchytreeus. 
VOL. 39, PART 1,—NEW SER. E 
