1887] Zoology. 669 
two legions,—1, Monopylea, or Nassellaria, with six orders, and, 
2, Cannopylea, or Phzodaria, with four orders. 
The immense amount contained in this work can be readily 
seen from the fact that these twenty orders are in turn subdivided 
into eighty-five families, seven hundred and thirty-nine genera, 
and four thousand three hundred and eighteen species; but 
large as these numbers are, Professor Haeckel doubts if they 
include half of the recent species. The ancestral group from 
which all the others are probably derived is the spherical Actissa, 
the most ancient stem form of the Spumellaria. The literature 
of the Radiolaria is not very extensive, only sixty titles being 
catalogued from 1834 until the present date. In the bibliography 
isa “ Phaulographic Appendix,” a division which embraces “ abso- 
lutely worthless literature,” a feature which might well be adopted 
in other bibliographies. The beautiful plates which illustrate the 
volume show what a field there is in these minute forms for the 
artist, 
Ctenodrilus parvulus.—Under this name Dr. Robert Scharf 
describes* a new species of Oligochete worm, probably from 
some part of the British coast, though the exact locality is un- 
known. The species differs from the two species (Ct. pardalis 
and Cz. monostylos) in its smaller size, having but from seven to 
ten segments, and a total length of about 4 mm. It has but one 
kind of seta, which are not pectinated, and it differs from mono- 
stylos further in lacking the peculiar tentacle found in that form. 
harf concludes that the number of sete in a bunch is not a 
good diagnostic character. There is but a single pair of ne- 
Phridia, which lie in the head. As in the other species the 
nervous system lies entirely in the ectoderm, and in some regions 
it is difficult to say where epidermal cells end and nerve-cells 
egin. No traces of reproductive organs were found, the only 
mode of reproduction being that by fission, which took place much 
as described by Kennel in Ct. pardalis. A bud is formed between 
two segments, and, in contradistinction to the Naidæ, these buds 
-are formed in the same order that the new segments are formed, 
—+¢., from in front backward. The first three segments never 
Show any signs of budding, nor do the last two or three. The 
buds appear on the anterior dorsal margin of each segment, the 
Segmentation of the body becomes deeper, and soon the body 
divides, the resulting portions developing the parts necessary to 
‘make them perfect worms. The process occupies about forty- 
eight hours. 
_ Balanoglossus Larvee.—Mr. W. F. R. Weldon gives a pre- 
liminary account of two Balanoglossus larvae (Proc. Roy. SaCy-s 
No. 253) which he obtained in the Bahamas, and which differ 
es cody 1 Quarterly Jour. Micros. Sci., xxvii., March, 1887. 
_ VOL, XXL—No. 7. 45 
