58 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
cubical epithelium ; the fold the author calls the pouch of the primary 
stilet. 
The hinder fold of the evagination has no lumen, but its cylindrical, 
non-glandular cells are closely pressed against the support of the stilet. 
The reserve stilets found in some Nemertines are formed in the pouch 
of the primary one, and are of the same size as it. The glands con- 
nected with the support of the stilet form that organ. 
The author thinks that the present condition was, phylogenetically, 
preceded by one in which the proboscis contained several pouches which 
formed stilets, and were of the same structure throughout. At a later 
stage one pouch became differentiated from the rest by forming in the 
hinder part of its glandular wall a firm secretion ; this secreted mass, or 
support of the stilet, took on an oval form. Later on, the stilets were 
only formed in the anterior part of the pouch. In the primitive Hoplo- 
nemertine the epithelium of the proboscis did not consist of glandular, 
but of supporting cells, and a remnant of that condition is to be seen in 
the pouch of the support of the stilet. 
Mr. Montgomery has not been able to see how the secondary stilets 
function in the living animal, but it is probable that they are weapons of 
less importance than the primary stilet. Further details are promised. 
Development of Tsenia anatina.* — Herr J. E. Schmidt has been able 
to follow the life-history of this tapeworm by infecting Cypris ovata Jur. 
with the eggs. The cysticercoids are also known to occur in Cypris 
compressa and C. incongruens. Two great periods in the development 
may be distinguished — that of all-round growth and that of growth in 
length. In the first period there are three stages, that of the still moving 
embryo, the solid germinal sphere, and the hollow sphere. In the 
second period, Schmidt distinguishes (1) the stage in which the rudi- 
ments of the most important “ vegetative and animal ” organs are estab- 
lished (excretory system, annular muscles, spindle-cells) ; (2) the stage 
during which the anterior region and attaching structures are differen- 
tiated ; (3) the third stage of maturation, when the cysticercoid takes its 
final form and becomes encapsuled. Two processes of folding must be 
distinguished, ( a ) the infolding of the anterior end to form the head, and 
(b) the purely protective infolding of the anterior region within the 
posterior, two processes which are quite distinct, though they occur 
together. Herr Schmidt describes the mature cysticercoid and the 
structure of the Taenia. 
Echinoderma. 
Holothurians from the Eastern Pacific. j — Prof. H. Ludwig has 
published in detail, and with great wealth of fine illustrations, his report 
on the Holothurians collected by the ‘Albatross’ in 1891, under the 
charge of Prof. Agassiz. As we analysed the preliminary notice at 
the time of its appearance J at some length, it is not now necessary to 
go into details. The genus called Mesites in the "preliminary report is 
now called Mesothuria, as Mesites is already in use for a Cystid. 
* Arch. f. Naturges., lx. (1894) pp. 65-112 (1 pi.). 
f Mem. Mus. Comp. Zool., xvii. No. 3 (1894) 183 pp. and 19 pis. with 
descriptions. J This Journal, 1893, p. 484. 
