864 THE AMERICAN NATURALIST. [ VoL. XXXV. 
The treatment of the limicolide groups should prove especially. 
interesting to the American students, as the scattered literature of 
these groups is especially difficult of access, as much of it is in Slavic 
languages. We are glad to see that the genus Ilyodrilus has been 
restricted to its three California species and separated from Bran- 
chiura, with which genus it has really no affinity. The treatment of 
Enchytrzidz is especially good, the author having previously studied 
this family, and being the first one to bring order out of the chaos 
which existed previous to his monograph on that family. Among 
innovations we remark the genus Lumbricillus substituted for 
Pachydrilus. It is to be regretted that this change should have 
been necessary, as we have already too many names with a similar 
sound. The family which probably interests us most is the large 
one of Megascolecide. This family is made to contain the majority 
of North American terrestrial earthworms. The most interesting 
fact connected with the family as defined by the author is that it is 
made to contain Ocnerodrilus as well as Diplocardia, Trigaster, 
Plutellus, Chilota, etc. The genus Achantodrilus, which a year ago 
contained more species than almost any other genus, is now restricted 
to a single species. The Old-World species of the once large genus 
have now been separated from the New Zealand ones, while the 
majority of the species have been referred to the genus Notiodrilus, 
etc. It is most interesting to note that as a result of the author's 
investigations we now find Achantodrilus placed next to Microscolex 
and its allied genera, while a few years ago these were referred te 
different families. The genus Plutellus has been resurrected, as 1$ 
quite proper, but what will astonish the general student more is that 
Plutellus and Pheretima have been referred to the same family, — 
the reason being that we now place very little importance on the 
number of seta in each somite, as long as the interior organs resem- 
ble each other. ‘The author has had special opportunity to examine 
Kinberg’s types in the Stockholm Museum. As a result of this 
investigation it has been possible to identify nearly all of Kinberg's 
genera and most of his species, and consequently many later names 
have to give way to the old Kinberg names, — Pheretima instead of 
Perichzta, etc. The subfamily Diplocardinz has been well treated, 
and so has its near relative Trigastrine. The Zapotecia has been 
raised to a full genus, it previously having been considered a sub- 
genus only. Dichogaster is made to contain both Benhamia and 
Dichogaster, which certainly is an easy way out of the difficulty in 
defining the relationship of these two genera. But even the author's 
