Hardening- of the Skin. Iclithyosis. 897 



vesicles filled with reddish fluid appearing round about the angles of the mouth, 

 and by the loss of hair in the att'ected places. The formation of vesicles as well as 

 the falling out of hair progressed in the direction of the lymph vessels up to the 

 ear region; aside from intense itching there was acute swelling of the lymph vessels, 

 of the lymph glands and of the parotid region, and disinclination for food. Re- 

 covery always occurred in a few weeks.— (Scheferling, Z. f. Vk., 1903, 322.) 



In two cases in old Scotch terriers the authors have had the opportunity of 

 observing a peculiar skin disease leading to the formation of multiple abscesses. 

 With the exception of the ends of the extremities the whole of the body was 

 studded with pea to walnut sized hard, painful nodules, which l)ecame softer as they 

 gradually increased in size and finally fluctuating. They ruptured early and dis- 

 charged a thin fluid pus mixed with blood and harboring fine diplococci. The loss 

 of substance healed slowly, and not at all in one case; the open patches gradually 

 increased in size and at their borders the skin was undermined in spots. Owing to 

 the constant new-formation of nodes and abscesses one dog died of exhaustion, the 

 other recovered. Fever was absent in both cases. The disease could not be pro- 

 duced artificially by intravenous and subcutaneous inoculation of the abscess con- 

 tents. 



A similar disease has recently been described by Cuille (Rev vet., 1905, 750), 

 who proved that the disease was caused by the bacillus necrophorus alone or by this 

 and pyogenic st'-eptococci and staphylococci. 



16. Hardening- of the Skin. Scleroderma. 



Gabarret and Lecuyer described a skin disease of swine which 

 occurs especially in old boars and gradually leads to hardening and 

 thickening of the skin. Starting from a spot in the middle line of the 

 back, the process gradually progresses forwards and backwards, as well 

 as on the sides of the body. At first the skin is firm, cool and moist 

 later on, however, it becomes dry, very firm and can no longer be picked 

 up in folds. Together with the gradually increasing thickening of the 

 skin (up to 5 cm. thick) the subcutaneous connective tissue atrophies, 

 the fat layer disappears almost completel.y, and the shrunken skin is in 

 almost immediate contact with the bones. The animals become greatly 

 emaciated and finally die. The thick skin is extremely hard to cut, the 

 cut surface shows a lardaceous luster and is pure white in color. On 

 cooking it does not become softer, but harder. According to Basset 

 this is a physiological process met Anth in all boars. (Basset, Bull, 

 1910, 44.— Lecuyer, J. vet., 1882, 300.) 



Pflug saw a similar disease in a calf. 



Ichthyosis. (Fish scale disease.) This disease was observed in newborn 

 calves whose skin was covered to a variable extent with horny scales 1 mm. thick, 

 and as a result appeared very rough and stiff. The gray or bluish scales of epidermis 

 formed narrow bands separated from one another by narrow grooves or clefts 

 which were arranged vertically to the axis of the body. The cause of the affection 

 lies in an unusual hyperplasia of the papillse of the skin, which leads to the formation 

 of a very thick and horny epidermis. In the cases which hitherto have been ob- 

 served the calves lived only 1 to 4 days. In a case noted by Sand the sharp edged 

 scales of the calf injured the mucous membrane of the genital passage during par- 

 turition. (Sand, D. Z. f. Tm., 1893, XIX 111.) 



Acanthosis Nigricans. (Keratosis nigricans; papillary and pigmentary 

 dystrophia.) This abnormality consists in a s^^nmetrical bilateral hypertrophy of 

 the papillary bodies, increase of pigment in the stratum corneum and germinativum 

 of the epidermis, further, contrary to the like-named disease in man, also in an in- 

 crease of pigment in the papillary bodies, round about the glands and blood vessels, 

 and finally in a moderate thickening of the horny layer chiefly in the furrows of the 

 skin. This disease was first described in veterinary literature by Schindelka and 

 was recently studied by Habacher. At the Vienna clinic seven eases occurred in 

 the course of ten years; and the authors have observed three cases. It develops 



Vol. 2—57. 



