982 W. C. M INTOSH. 
nal coat, d, comes next; then the fifth layer of circular mus- 
cular fibres, c, with the basement layer, 6', and a beautiful 
papillose glandular lining, 4, internally. ‘Very fine fibres 
pass from the base of the glandular papille to the circular 
muscular coat. I have been thus particular in specifying 
the layers (or repeating, as they correspond with previous 
remarks) because my friend Dr. Hubrecht in a recent pub- 
lication! has put forward views—based on the examination 
of this form—which diverge wholly as regards the structure 
and function of the reticulated layer of the proboscis of the — 
Enopia. He considers the layer as glandular, and an inspec- 
tion at his drawing (op. cit., Plate II, fig. 2) shows that a mis- 
interpretation has occurred. If the proboscis of this or any 
other typical member of the ENopia be examined in the 
fresh condition, a number of longitudinal bands at regular 
intervals are very conspicuous in the anterior region. These 
are the thick columns (e) of the reticulated layer. If a 
longitudinal slice be taken from the proboscis of Amphiporus 
pulcher (Plate XIV, fig. 4), the same columns form a series 
of boldly marked longitudinal bands (e e) connected together 
by numerous transverse slips (é e’), which unite the ‘longi- 
tudinal columns. In transverse section these bands, as 
already seen, completely separate the longitudinal mus- 
cular fibres of the proboscis into two layers, and in none 
are they better seen than in Dr. Hubrecht’s specimen. 
The latter author, therefore, in representing (op. cit., 
Plate II, fig. 2), and describing the great longitudinal 
bands of this layer as isolated glands, had omitted to make 
a longitudinal section or examine the proboscis in transverse 
section with sufficient detail, for he overlooks the connecting 
bands (e, ¢ e’,) between the longitudinal columns. In no 
group is 1t so necessary as in the Nemerteans to examine an 
extensive series of the animals and their organs under vary- 
ing conditions, both during life and after preparations. 
Iam glad to see that my friend in his present communi- 
cation to this Journal has now retired from the foregoing 
position with regard to the reticulated layer. A careful 
examination of longitudinal and other sections would cer- 
tainly convince him. I must demur, however, to the some- 
what doubtful remark that the longitudinal columns of this 
layer are “ surrounded and united by bands of fibrous elastic 
tissue which at the same time traverse the longitudinal mus- 
cular coat in all directions, and originally depart from the 
external and internal circular layers of elastic tissue.”” We 
have already seen how this “fibrous elastic tissue” has fared 
1 « Aanteekeningen,’ &c., olim cit. 
