1881. | Zoology. ers 
sons which he assigns, that at an earlier embryonic date there 
were a longer notochord, a longer medullary tube and a greater 
number of primitive or proto-vertebrae. In an embryo a few weeks 
older, on the other hand, the notochord would entirely disappear. 
Haeckel’s view, therefore, is, so far as one abnormal example is 
concerned, apparently sustained against that of His. 
New Type or Parasitic CrusTacEAN.—A new parasitic Cirri- 
ped (Laura) has been discovered by Lacaze-Duthiers, according 
to the Journal of the Royal Microscopical Society, living as an 
Antipatharian coral (Gerardia), Externally it is kidney-shaped, 
and its body, composed of twelve segments with six pairs of 
limbs, is imbedded in the soft parts of the coral; it is a little over 
a centimeter long, with a carapace formed of two scales or valves 
united along the median line, and is from two to four times as 
long as the body. The carapace is hard externally with a soft 
internal layer; between these there is lodged the liver and one o 
the genital glands, together with a very rich vascular plexus, The 
external covering is riddled by a large number of small ducts, the 
Outer orifices of which are covered by a membrane, which is sur- 
rounded by delicate filaments; these are of a cartilaginous con- 
sistency, and have a central duct. A study of the circulatory or- 
the tissues of the coral. The peculiar arrangement of the digest- 
tion with the cilia beneath which they course. This connection 
Engelmann could not confirm, Certain it is that the ciliary move- 
eat. of Stentor are independent of the general contractions of 
dy. 
Do the Infusoria possess an approximation to the nervous sys- 
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