STUDIES ON EARTHWORMS. 231] 
Hutton (35) has described four Earthworms which he refers 
to the genus Lumbricus, but they seem to belong to various 
genera. L. uliginosus has four male pores, two being in 
somite 1x and two in somite x. L. campestris has a pair 
of male pores in somite rx. 
In 1878 Perrier described a new genus (27), of which only 
one species is known—Plutellus heteroporus, from Penn- 
sylvania. Length 15 cm., breadth 3 mm. The clitellum 
occupies somites XIV, XV, XVI, XviI, and is complete. The 
setz are eight in each somite, at nearly equal distances apart, 
and do not alternate. The nephridiopores vary in position. 
The first four pores are in a line with the third seta from the 
ventral mid-line. The rest alternate in successive somites, one 
series being in line with the second seta, the other series being 
in line with the fourth seta. The spermathecez are five 
pairs in somites v, vI, VII, vi11, 1x, their pores being in the 
anterior region of these somites in line with the second setz (i.e. 
with one set of nephridiopores). Hach spermatheca consists 
of a sac and a short, slightly swollen blind tube opening into 
its neck, resembling the arrangement in some Perichetz. The 
male pores are, in somite xvii1, dorsad of the first sete 
counting from the ventral mid-line. There are no papille. 
The female pores are in somite x, in line with the first sete. 
The seminal reservoirs are a single pair of grape-like 
glands in somite xu. There is a prostate and a penis 
in somite xvi1. The nephridia do not pass through the 
anterior septa, but lie wholly in one somite. 
Perrier regards this genus as very likely the same as Kin- 
berg’s Hypogzon, as opposed to the similarly named genus of 
Savigny. 
In 1874 Perrier published an abstract in the ‘Comptes 
Rendus’ (13), and in 1881 a detailed account (29) of a worm 
which lives on the seashore at Marseilles. He named it 
Pontodrilus Marionis. Its length is 80 mm., and breadth 
4mm. It consists of fifty somites. The clitellum occupies 
somites x11 to xvi1. The setz are rod-like. The ventral 
couple (1 and 2) are close together, but the other two (3 and 
