ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
347 
and Nearctic regions, which necessitates their fusion into a Holarctic 
region ; (2) the separation of Japan from the Palaearctic and its relega- 
tion to the Oriental region ; (3) the great richness of South America 
and Australia in peculiar types ; (4) the wide distribution of Acantho- 
drilus in the land masses of the southern hemisphere, which agree in 
the great abundance of species of this genus and comparative rarity of 
other forms ; and (5) the marked difference between New Zealand and 
Australia. 
Structure of New Earthworms.* — Mr. F. E. Beddard gives an ac- 
count of the structure of two new genera of Earthworms belonging to 
the Eudrilidae and coming from Lagos, West Africa. These new genera 
he calls Heliodrilus and Hyperiodrilus. As in other Eudrilidae, and 
them only, the epidermis is furnished with peculiar organs which may 
be sensory ; they have some resemblance to the Pacinian bodies of 
Vertebrates, and are scattered irregularly over the surface of all the seg- 
ments except the first. There is only one pair of calciferous glands ; in 
each of the tenth, eleventh, and twelfth segments there is a median 
diverticulum of the oesophagus ; the epithelium of this is so folded as to 
present the appearance of a series of parallel tubes : the peripheral cells 
are excavated and form a ramifying system of ductules. There is no 
anterior gizzard, but there are six segmentally arranged gizzards at the 
junction of the oesophagus and intestine. 
The supra-intestinal blood-vessel in the oesophageal region is in- 
closed in a special coelomic compartment, which is almost filled by 
nucleated corpuscles. The male genital pore is single and median on 
segment xvii. ; the “ atria ” are glandular and very long ,* there are no 
penial setae, but in Hyperiodrilus there is a penis in the form of a hollow 
process of the body-wall. The ovaries are inclosed in special coelomic 
sacs which communicate with the egg-sac, and are prolonged dorsally so 
as to entirely or partially inclose the single spermatheca which opens 
on the middle line. In Hyperiodrilus the perigonidial sacs form a ring 
round the oesophagus, and are connected with a dorsal unpaired sac. 
Mr. Beddard has been able to examine some specimens of Nemerto- 
drilus which may be referred to the Eudrilidae for several reasons ; the 
absence of certain characters ordinarily seen in Eudrilids is perhaps a 
sign of degeneration. 
Structure of Deodrilus and Anal Nephridia in Acanthodrilus.f — 
Mr. E. E. Beddard describes an Oligochaete from Ceylon, which, on 
account of its intermediate characters, he calls Deodrilus ; the species is 
D. Jacksoni. It is most closely allied to the Geoscolecidae and Eudri- 
lidae as lately defined by Rosa. Like some of the former it has no 
prostomium ; in the characters of its clitellum, &c., it is intermediate ; 
the possession of ornamented setae shows its affinity to Ehinodrilus ; in 
the presence of a diffuse nephridial system it resembles certain genera 
of the Eudrilidae. Concise definitions of the genus and species are given. 
In a specimen of, apparently, Acanthodrilus multiporus tubes of 
precisely the structure of nephridia and communicating with the 
general system may be followed, through the lining epithelium of the 
* Quart. Journ. Micr. Sci., xxxii. (1891) pp. 235-73 (5 pis.). 
t Op. cit., xxxi. (1890) pp. 467-88 (2 pis.). 
