68 W. CO. MCINTOSH. 
brownish pigment-rings. The following segments have lateral 
touches of the same colour, which posteriorly almost assume the 
form of rings. The tip of the tail is brownish, and the same 
tint occurs anteriorly at the lips of the proboscis. 
His next stage presents elongated tentacles with long 
papilla and coiled like ram’s horns, yet the snout is even 
shorter than in the foregoing stages, so that a certain amount 
of variation exists. The length is 8 mm., and it swims like an 
eel. Claparéde compares the elongated papille with the 
peculiar “stabchen ”’ on the tentacles of Spio as described by 
Strethill Wright, but the differences are considerable. The 
first body-segment bears the long bristles. From the second 
to the eighth segment the lateral bristles have disappeared. 
From the ninth to the fifteenth long provisional bristles as well 
as hooks with an elongated shaft are present. The brownish 
glands behind the proboscis are larger. The blood has a bluish 
appearance. The end-segment is hoof-like and somewhat 
resembles that of Leucodore, and it has small coloured 
warts. 
He concludes by mentioning that further stages of Mage- 
lona were not got in his nets, and that they probably took to 
the bottom to burrow in the sand at the extreme margin of low 
water. He was inclined to relegate the larva to the Spionidze. 
On the present occasion only the more advanced S pio-like 
forms, approaching Claparéde’s two last stages, figured in his 
pl. x, figs. 10 and 12, will be dealt with. The first was 
obtained on the 28th May, and had about twenty-five segments 
exclusive of the head and tail. The animal (PI. 8, fig. 1) is 
nearly translucent, faint touches of white pigment appearing 
on the sides of the proboscis posteriorly, at the commencement 
of the narrow part of the gut, and at the base of the tentacles. 
An opaque white mass (the contents) also marks the centre of 
the gut towards the tip of the tail. Lateral opaque white 
specks in groups further indicate the segments in the anterior 
(dilated) region of the body. ‘The latter consists of nine seg- 
ments, the tenth being opposite the whitish opacity (a, Pl. 8, 
fig. 1) marking the commencement of the constricted portion 
