Literary Notices. xxv 



Giaconini ' formulates the following statements : 



1. Microcephalism is essentially located in the central nervous system. 

 2. The deformity of the skull is a result not a cause. 3. The disturbance 

 is not limited to the 'brain but extends to other parts of the nervous sys- 

 tem. 4. Microcephalism consists in a retardation in the development of 

 the central system, beginning at various periods. 5. The nervous system 

 exhibits no pathalogical condition explainable as a result of complete 

 arrest of the development. 6. The lirains of microcephalic subjects 

 exhibit all the stages of human brain development from the earliest on. 

 7. In the structure of the surface there are modiHcaiions which must be 

 referred to atavic reproduction of conditions of the brain of lower 

 animals. 



The work of Marchand given in the literature furnishes illustration of 

 the above points. An abnormal development of the callosum is very 

 common, the curtailing of the length being associated with modifications 

 of the fornix. In the absence of the callosum the median fissures, etc., 

 are radially arranged The frontal lobe usually exhibits three well- 

 marked fissures even in extreme cases. 



Mingazzini describes in the Intcrnation. Monatschrift f. Anatoinu u. 

 Physiologic, VII, i;, an interesting brain from an 1 i months idiotic child 

 in which there were abnormal convolutions, absence of the callosum and 

 praecommissure ; rudimentary septum pellucidum ; atrophy of the left 

 tuberciilum anterior of the thalamus, ganglion habenuliP, both (juadrige- 

 mina; absence of fornix commissure and olfactory .tract ; atrophy of the 

 left hemisphere of the cerebellum, left inferior olives, clava, tuberculum 

 rolandi and eminentia acustica ; reduction in the left optic tract and left 

 pons peduncle, etc. 



Mingazzini and f'erraresi take the occasion afforded by the description 

 of an ape-like brain of a 16 years microcejjhalic child to distinguish twO' 

 types of such abnormalities: i, reductions in the size and simplification 

 of structure without loss of the human type, 2, those in which there is ani 

 obvious approach to the structure of the brain of lower apes or the 

 carnivora. 



1. Studio anatoniico dolla niicroeefala. Heale Accatl. di lucdiciiia di Torino, 



ISilO. 



