THE CALCIFEROUS GLANDS OF EARTHWORMS. 
457 
(3) Descriptions of the form and situation, and sometimes of the disposition of 
the lamellae, of the glands in various genera and species, in systematic papers ; these 
occur in abundance, since the organs are of importance from a systematic standpoint, 
but they do not give any histological detail. 
( 4 ) Papers on the physiology of the glands. 
Of these, the last three do not concern us, and even of the first group it is 
scarcely possible to give an adequate account here. All that will be attempted is 
to give a short resume of the work of previous investigators on forms which are 
either those or allied to those which we have ourselves examined. This will be most 
suitably done in the body of the paper, as we take up the various types of structure. 
Material and Methods. 
We have investigated the following : — (l) Pheretima haway ana (Rosa), a widely 
distributed species of the Megascolecine branch of the Megascolecidse ; it is perhaps 
the commonest earthworm in Lahore, and the genus is the one which is studied as a 
type in the colleges of Northern India. (2) Ocnerodrilus ( Ocnerodrilus ) occidentalis 
Eisen, found sporadically in India ; it belongs to the Ocnerodriline branch of the same 
family ; it was not known to occur in the neighbourhood of Lahore till the course of 
the present inquiry, when some small worms, supposed to be immature Helodrilus 
parvus , were subjected to examination ; these proved to be 0 . occidentalis. (3) Octo- 
chsetus barhudensis Stephenson (Octocheetinse, a sub-family of the Megascolecidse) has 
been described by one of us from the Chilka Lake, on the east coast of India. It is 
a small worm, and had to be investigated by means of sections ; these, prepared for 
the purpose of the systematic description of the worm, have been used for the 
present paper. (4) Eutyphoeus , waltoni Michaelsen, also belonging to the Octo- 
chsetinse ; it is common in the United Provinces, and the genus occurs here and there 
in the Punjab, but it is not known from near Lahore. We owe our specimens to the 
kindness of Professor Yotjngman, of the Department of Biology, Canning College, 
Lucknow. (5) Two species of Helodrilus which we have examined, H. ( Bimastus ) 
parvus (Eisen) and H. ( Allobophora ) caliginosus (Savigny), are common in Lahore. 
(6) Lumbricus sp., kindly sent us by Dr J. H. Ashworth, E.R.S., from Edinburgh ; 
the worms were not fully mature, and the species was therefore not determinable. 
Previous workers have recommended the avoidance of acid fixatives, as these 
destroy the calcareous concretions both before and after their discharge from the 
cells ; the precaution as to acid fixatives has most force in work done with a physio- 
logical end in view, and it seems rather fanciful to say, as Combault does, that 
treatment with such an agent causes the epithelium of the glands to take on the 
appearance of a vascular endothelium. We have, however, used formalin mainly as 
a fixative for the worms that we have ourselves preserved ; but in a few cases where 
we have used sublimate and acetic acid we cannot point to any marked differences 
