No. 402.] REVIEWS OF RECENT LITERATURE. 527 
of the eyes does not alter this reaction, so that orientation is not 
accomplished in these forms by the eye, as in many other animals. 
The loss of one otocyst does not affect the animal's movements, the 
remaining one being sufficient to keep it normally oriented. P. 
Capillaries and Sinusoids. — C. S. Minot! draws attention to the 
fact that in the vertebrates blood vessels are connected not only by 
capillaries but also by irregular, minute spaces, for which he proposes 
the name “ Sinusoids." The walls of a sinusoid, like those of a capil- 
lary, are formed from a single layer of endothelial cells, but the 
capillary wall has the form of a tubule, while that of the sinusoid 
follows the irregular surfaces of the tissue spaces in which it lies; 
capillaries are tubules, but sinusoids are irregular, branching systems 
of spaces.  Sinusoids form the main blood channels in the pro- 
nephros, mesonephros, liver, heart, supra-renal capsules, parathyroid 
glands, carotid glands (probably), and coccygeal glands. P. 
Villi of the Mammalian Intestine. — The development of the 
villi in the intestine of man and of the pig has been investigated by 
J. M. Berry." The inner surface in young embryos is at first smooth, 
but afterwards becomes thrown up into longitudinal folds, such as 
are found permanently in many of the lower vertebrates. These 
folds increase in size and then break up into rows of villi. After 
the first villi become fully developed, new ones are added to the 
intestinal surface, so that fully developed villi and forming villi may 
be found side by side, the number of the villi thus increasing with 
increase of age. DE. 
Notes. — Dr. Kishinouye has described (Proc. U. S. Nat. Mus., 
Vol. XXII, p. 125) a new species of stalked jellyfish, Ha/iclystus stej- 
negeri. This genus has thus far been represented by three Atlantic 
species. The new form comes from the Commander Islands in the 
Pacific. 
The distome genus Clinostomum, founded in 1856 by Leidy, 
has been brought forward again by Braun (Zool. Anz., Bd. XXII, 
! Minot, C. S. On a hitherto unrecognized Form of Blood Circulation without 
Capillaries in the Organs of Vertebrates, Proc. Boston Soc. Nat. Hist., vol. xxix, 
pP. OPES d 1900. 
rry, J. M. On the Development of the Villi of the Human Intestine, 
Anat. Anz., Bd. xvii, pp. 242-249, 1900. 
