SUMMAKY OF CURRENT RESEARCHES. 435 



True Hermaphroditism in Man and Mammals.* — Ludwig Pick 

 takes a critical survey of the available facts in regard to hermaphrodi- 

 tisrnus verus in man and mammals. What is meant is the occurrence of 

 definite male and female gonads in the same individual. Whether they 

 produce gametes or not is another question. Organs which are charac- 

 teristically testicular should be ranked as testes even if they produce no 

 sex-cells. All gradations occur. Eleven cases of true germinal or 

 gonadial hermaphroditism are known in the pig and three in man. It 

 may be bilateral, with an ovotestis on each side ; or unilateral, with 

 testis on one side and ovary on the other. In Salen's case in man, the 

 ovotestis on the right side had a functional ovary, and the tubules of 

 the testicular part contained some indubitable spermatogonia. But we 

 cannot do much more than refer to the author's very careful discussion 

 of an intricate subject. 



Hermaphroditism in a Dogfish.f — A. Vayssiere and G. Quintaret 

 describe what is a very rare occurrence — hermaphroditism in Scyllium 

 stellare. The fish was on the whole a female, but the right pelvic fin 

 showed a " clasper," and the ovary had attached to it a well-formed 

 testis. There were two normal oviducts, and there was a single vas 

 deferens (to the right) which had no connexion with the ureter. 



Blood-formation in Embryonic Liver.f — R. Haff finds that the 

 liver of the embryo chick shows two periods of blood-making. The 

 first begins about the middle of the seventh day of incubation and lasts 

 till the beginning of the ninth day. There are numerous erythropoietic 

 groups and a sparse granulopoiesis. The capillary endothelium and the 

 peritoneal enveloping cells produce a reticular tissue, which is the start- 

 ing point of the hgeniatopoiesis. 



From the indifferent connective tissue cells there develop the mother- 

 elements of the blood, and from these through diverse stages of 

 differentiation the red and white blood-corpuscles. The elements of the 

 erythrocyte series appear in an extravascular reticulum, the open mesh- 

 work of which bounds the vascular spaces, and they pass thence into the 

 blood-stream. 



The newly formed connective tissue does not extend through the 

 whole organ at the time of the most intense blood-formation ; especially 

 in the central portions of the vascular area it retains its original closed 

 character. About the middle of the ninth day the organ returns to its 

 original indifferent state. About the eleventh day an intense granulo- 

 poiesis sets in, which reaches a climax about the fourteenth or fifteenth 

 day. It wanes towards the end of the embryonic development. 



Origin of Supra-cleithral Bones from EpidermisJ — B. Haller 

 supports the view of Klaatsch that skeletal parts may arise from the 

 epidermis. In the case of the supra-cleithral bones of the trout, he is 



* Arch. Mikr. Anat., lxxxiv. (1914) 2te Abt., pp. 119-242 (5 pis. and 5 figs.), 

 t Comptes Rendus, clviii. (1914) pp. 2013-4. 



X Arch. Mikr. Anat., lxxxiv. (1914) 1.te Abt., pp. 321-50 (2 pis.). 

 § Arch. Mikr. Anat., lxxxiv. (1914) lte Abt., pp. 446-52 (1 pi.). 



2 G 2 



