564 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Mouth and Pharynx of Hamster.* — P. Roscher describes the whole 

 anterior region of the alimentary system in Cricetus frumentarius — the 

 cheek-pouches, tongue, teeth, glands, etc. The cheek-pouches are for 

 transport to the place of storage ; they have nothing to do with diges- 

 tion. They might be compared to a paunch. The buccal glands are 

 highly developed. Minute descriptions are given of all the parts. 



Kidneys of Fishes.t — Frederic Guitel describes the kidneys of 

 Aphya pellucida, A.ferreri, Tripterygion nasus, and Glinus aryentatus. 

 In at least three of these {Aphya ferreri is doubtful) the kidney is a 

 persistent pronephros. 



Venous System of the Lamprey.} — B. Mozejko gives a preliminary 

 account of part of this system. He deals with the abdominal venous 

 sinus, the hepatic veins, the anterior cardinal or jugular veins, the 

 ventral jugular vein, the peribranchial cavities, the median sinuses, the 

 sinuses at the anterior end of the head, the orbital sinuses, and the 

 facial veins. 



Tunicata. 



Development of Salpa Chain.§ — Myrtle Elizabeth Johnson describes 

 the manner and rate of growth of the zooids of the chain of Salpa fasi- 

 formis-runeinata. Some account is also given of chains of S. zonaria- 

 cordiformis and S. cyiindrica. Some of the chief observations are 

 summarized as follows : — 



The chain of Salpa fusiformis-runcinata is made up of a series of 

 blocks, the zooids of each block being approximately the same size. 

 Between the last two blocks is found a short piece, the intermediate 

 piece, containing imperfect or undeveloped zooids, while in the proximal 

 portion of the chain is a deploying point where the zooids change from 

 single to double file. A terminal remnant of imperfect zooids is found 

 at the distal end of the chain, unless the distal block is the first one 

 produced. The unsegmented chain consists of a tubular sheath of ecto- 

 derm enclosing strands containing the various embryonic elements. The 

 chain elongates and becomes cut up into a series of segments, each con- 

 taining its share of the embryonic elements. This segmentation is 

 initiated and carried on by the infolding of the ectoderm. As the 

 zooids grow, they push each other out of line so that they change from 

 a single file to double file. The regular segmentation of the proximal 

 portion of the chain is sometimes interrupted by an unsegmented space. 

 The blood tubes, which run through the chain, grow smaller and dis- 

 appear before the zooids are set free. This disappearance begins at the 

 distal end. As the vascular connexion disappears, papillas develop, 

 which unite adjacent zooids and may or may not furnish nutritional 

 connexion. The zooids at the ends of the block are much smaller than 

 the intermediate zooids. The maximum size (length or width) is near the 

 distal end in the younger blocks. In one block of large zooids the 

 maximum size is near, though not at the proximal end of the block. In 



* SB. k. Akad.Wiss. Wien, Math-Nat. Classe, cxviii. (1909) pp. 441-504 (2 pis.). 



f Arch. Zool. Exper. , v. (1910) Notes et Revue, pp. i.-x. (1 fig.). 



% Anat. Anzeig;, xxxvi. (1910) pp. 618-4.3 (4 figs.). 



§ Univ. California Publications (Zool.) viii. (1910) pp. 145-76. 



