_Rickets._--The chief characteristic of this condition is defective ossification. Instead of possessing their usual rigidity, the bones become curved, and multiple deformities result. The legs become bowed, and the knees cannot be brought into contact when the feet are placed together; the thorax becomes constricted or gibbous, etc. In addition to the nutritive disturbance, which appears to be at the root of all these disorders, there may be, according to some authors, an affection of the entire system, and especially of the nervous centres. Unfortunately, as rickets is a disease of the earliest years of life, one often finds oneself in the presence of the sequelæ which have been left, and which simply must be made the best of. _Adenoid Vegetations._--Everyone has now heard of cases of this kind where the appearance is so characteristic. The lips are always half open, the appearance is sleepy-looking, the respiration is difficult. If one looks at the throat, or if one introduces the finger into the child's mouth in order to explore the pharynx behind the soft palate, one will see or feel the large tonsils or the fleshy masses which obstruct the posterior orifice of the nasal fossa. One would like to find in these vegetations the cause of the habitual torpor of the children, and of their want of progress. It is true that there is a connection between mental backwardness and adenoids. The removal of the swellings by a surgical operation will make more free the respiration, whose obstruction prevented sustained attention, and will also frequently cure the deafness, which was due to an obstruction of the Eustachian tubes. The operation may therefore result in a marked amelioration of the mental condition as well as of the general health. If the amelioration is sufficient, the child can be sent back to the ordinary school. _Scrofula, Tuberculosis._--A child with a lymphatic appearance, whose tissues are infiltrated with serum, and whose glands readily become enlarged, requires plenty of country air and a nutritious diet. If he is admitted to the special school, it will be advisable to attend to his health before subjecting him to any particular educational methods. The doctor, then, will notice in passing the existence of such conditions as rickets, adenoids, and scrofula in the children who are submitted to him. Affections of the lungs and tuberculosis of the bones will also attract his attention. But such affections in abnormal children have no other significance than in the case of children of average intelligence. They furnish no special indication regarding the admission or non-admission of the child into a special class. Their severity alone determines the course to follow with respect to their treatment.