284 WwW. C. MINTOSH. 
(one of the Lineidz) “ the curious deviation of fibres from the 
internal and external circular muscular layers presented a 
somewhat different aspect” from anything that had been 
described. A glance at Pl. XXIII, fig. 17 (op. cit., Ray So- 
ciety), will remove doubts, for in that form (Cerebratulus angu- 
latus) the fibres cross exactly at opposite poles. It would be 
well also that Dr. Hubrecht should make various longitudinal 
sections of the proboscis of the foregoing Meckelia somato- 
tomus to see if the “ external circular muscular layer ” (e in 
his Plate II, fig. 7, op. cit.) really goes all the way round, 
because such is uncommon in the Anopla. At any ratea 
homogeneous elastic investment of the longitudinal layer 
immediately beneath is sure to be encountered. 
5. Digestive and Circulatory Systems. 
The digestive system in A. spectabilis agrees with that in 
the typical ENopia. 
The vascular system shows the usual central dorsal vessel 
beneath the proboscidian sheath, and a ventral on each side 
—hbeneath and internal to the nerve trunk, and in addition 
there are numerous accessory trunks. The coloured circulat- 
ing fluid in these vessels was first described in the allied 
species (Cerebratulus crassus) by M. de Quatrefages, and in 
the present form by Prof. Keferstein, who also mentions the 
corpuscles. Dr. Hubrecht and M. Marion confirm these 
observations. The latter, whose anatomy of the Nemerteans 
received attention in the Appendix (op. cit., Ray Soc., 
p- 213 &c.), in his most recent remarks! states “that the 
vascular apparatus of this Nemertean presents the surprising 
peculiarity of containing elliptical globules slightly flattened, 
and of ared colour identical with that of the blood-globules 
ofman.” “If we press down a part of the body, these cor- 
puscles accumulate in certain regions of the circulatory 
system, and form masses of an intense red colour. ‘The oscil- 
lations of the globules also may be followed by observing a 
young animal by transmitted light. The corpuscles are set 
in motion by a colourless liquid, in which they float without 
any constant direction.”” He then mentions a dorsal and 
two ventral trunks, with the transverse branches from the 
one to the other, but it would have been well if he 
had been a little more definite in his description 
of this course of the corpuscles in these vessels, and, 
moreover, if he had indicated the richly corpuscu- 
lated fluid within the proboscidian sheath. If a longitu- 
1 © Ann. Nat. Hist.,’ olim cit. 
