54 Williams, Fisher, and Udall: The Spavin Group. 
When active lesions are present the horse is unfitted for 
either work or breeding according to intensity. 
OTHER MALADIES POSSIBLY ALLIED TO THIS 
GROUP OF AFFECTIONS. 
In this great group of diseases it is not easy to definitely 
limit it in its scope. If, as alleged in this discourse, the disease 
is systemic in character, any tissue may stuffer. In the one 
case related and shown in Figs. XVII and XVIII, we stated 
that the various affections belonging to this group were revealed 
as a consequence of the presence of tendonitis and tendo-vagi- 
nitis. These affections seemed to be the initial appearances of 
interruption of the convalescence from contagious pneumonia. 
This tendonitis and tendo-vaginitis is a common complica- 
tion of contagious pneumonia, and closely associated with the 
appearance of the spavin group of lesions. Clinically they are 
closely related and seem to be due to the same causes. It is a 
common assertion, moreover, that in this group of lamenesses, 
the flexor tendons occasionally part, though in reality they 
generally merely pull away from the bone, carrying parts of 
osseous tissue along. 
Another interesting malady which appears in the region 
of Ithaca, New York, quite abundantly consists in the gradual . . «. 
sinking of the os pedis without history, of laminitis or other 
disease. It seems identical with what Moeller describes as 
sinking of the os pedis, and which is rendered by Dollar in his 
translation as standing laminitis. 
In cases which we have met, navicular disease is present, 
and it seems possible that in flat-footed horses, in attempting 
to throw the weight on the toe of the hoof, the os pedis slips 
backwards and then downwards, carrying the sole with it 
Moeller attributes it to standing on one foot while the corre- 
sponding member is disabled. As we have seen it here, both 
pedal bones sink simultaneously and insidiously without- dis- 
cernible cause, under the same conditions most common in 
the spavin group. . 
These addenda are only suggestions as to a possible rela- 
tionship which may yet prove of interest. 
