156 SUMMARY OF CURRENT RESEARCHES RELATING TO 



the cartilaginous* tissue of worms and some Arthropods, and the cartilage- 

 like tissue in some Arthropods and Coelentera. There is true cartilage 

 in Molluscs, Annelids, and the branchial skeleton of Limulus, but that 

 of the endosternite of Limulus and of Ostracods cannot be called more 

 than cartilage-like. In the latter there are some features which are 

 cartilage-like, such as the rounded-off shape and the vacuoles of Ostracod 

 cells, the arrangement of the cells in groups, and the capsule-like 

 thickening of the matrix around the cells of the endosternite in the 

 King-crab. In neither of the two kinds of tissue is there any trace of 

 chondromucoid substances, the capsule-like cell-membranes consisting 

 exclusively of collagen-containing substances. In the cartilage of 

 Cephalopods and in the peripheral portions of some sub-radular cartilage 

 in Gastropods there .are branched cells and abundant parenchyma ; in 

 the parenchyma-like cartilage in parts of Gastropods, Annelids, and 

 King-crab, the cells are rounded and unbranched. Both types correspond 

 to young or embryonic cartilage in Vertebrates. A full account is given 

 of the minute structure. 



c. Greneral. 



Vestiges of Scales in Siren.*— Margarethe Kressmann has made 

 the interesting discovery that the deeper and firmer layer of the corium 

 in Siren Jacertina bears vestiges of scales. These occur diffusely all 

 over the body, though sometimes with a hint of transverse rows. 

 They consist of dense connective-tissue and project into the loose upper 

 layer of the corium, which quite conceals them. Each is usually tipped 

 with a mantle of pigment. They are interpreted as vestiges of the 

 scaly armour of the extinct Stegocephali. 



Micro-fauna of Bolivia and Peru. f— James Murray and G. H. 

 Wailes report on collections of the little known micro-fauna of these 

 countries. The collections included 78 Rotifers, 16 Tardigrades, and 

 46 Rhizopods (including varieties). There were 124 from Bolivia and 

 42 from Peru. All these are new records for these countries, and 42 of 

 the Rotifers and 7 of the Tardigrades are new for South America. 

 There is some indication that there is an actual poverty of species, 

 perhaps in part due to the altitude, cold, and thin air of the "altoplanicie " 

 and the hills rising from it. 



Absence of Epiphysis Cerebri in some Mamnials.| — H. G. Creutz- 

 feldt finds that the pineal body is absent in Dasypus and in the Dolphin. 

 It is relatively small in elephant, rhinoceros, and tapir. In some Ceta- 

 ceans and in the Dugong, the epiphysis is absent ; in some other Ceta- 

 ceans it is relatively small. This is said to be the case in crocodiles 

 and in the torpedo. The author enquires whether the absence or 

 diminutiveness of the epiphysis may have to do with thickness of the 

 skin. In animals with smooth thin skin and smooth thick short hair, 

 the epiphysis is very strongly developed. 



* Jen. Zeitschr. Naturw., xlviii. (1912) i^p. 399-432 (1 pi. and 16 figs.), 

 t Notes on the Natural History of Bolivia and Peru. Edinburgh : Scottish 

 Oceanographical Laboratory (1913) 45 pp. (17 figs). 

 X Anat. Anzeig., xlii. (1912) pp. 517-2 L (4 figs.). 



