NOTES ON SOME AQUATIC OLIGOCHATA. 193 
the cheetz swell up to nearly twice their real diameter, so that 
this method alone would give a wrong impression as to their 
real shape ; the terminal parts appear to be harder, and are not 
so affected. 
Table of Arrangement of CHarta. 
Dorsal Bundles. Ventral Bundles. 
i= Se = ee 
Segment. Right. Left. Right. Left. 
Il. 2or3 2or3 3 or 4 3 or 4 
Ill. ai(--7 1) 4 (ctaulh), *13) Che? )t + 3. (re8) 
IV. 4(+ 1) 22 1))-wele= 2) e(G= 1) 
V. 6Gor7(+2or3) 6(+2o0r38) 8(+1) 4(4+)) 
VI. ah 3) SEe so) soca BE aE es) 
VIL 7 (+ 3) 10 (+ 1) 8(+ 1) 3(4+)) 
VIII. 9 (+ 3) 11 (+ 3) 3(+1) 8(4+1]) 
IX. 11 (+ 2) 11 (+ 1) 8(+1) 3(41) 
X. 9(+ 1) 9 (+ 3) 2 2 
XE. 6 (+ 1) 5 (+ 2) 2 (or 1) 2 
DAU 6 (+ 3) 6 (+ 2) 2(4+ 1) 1(4+)) 
XIII. 4 (+ 2) 6 (+ 1) 1(4+ 1) 1(4+) 
XIV. 3 3 (+1) 1(4) 
XV. 2 or 3 2or3 2 2 
XVI. 2 2 2 2 
XVII. 2 2 Q 1 or 2 
XVIII. Q 2 2 2) 
XIX to XXIV. Q 2 2 2 
XXV to end. PY 2 1 1 
Notre.—The strong figures represent the palmate chete; the (+ 2) repre- 
sents young chete, which do not protrude. 
But I have found, not unfrequently, examples which show 
a slight difference in the position of the palmate bundles. 
In two or three specimens the chetz of Segment xIv were 
palmate, like those of x11. 
In another specimen the dorsal bundle of one side of 
Segment xiv consisted of four palmate and one furcate chetze, 
that of the other side only of furcate chete. 
In another a similar asymmetry of Segment xv occurred; 
i. e. on one side the bundle consisted of one furcate and two 
palmate cheetz, those of Segment xiv being all palmate. 
VOL, XXXIII, PART I—NEW SER. N 
