146 SEVENTH REPORT—1837. 
by the eye through their whole course. When pus has been 
well removed from a suppurating surface its place is soon sup- 
plied by a thin and watery secretion. This afterwards becomes 
viscid, but without being visibly particled; it afterwards be- 
comes manifestly particled and turbid, and ultimately thick, 
opaque, and cream-like. There are perhaps no secretions which 
are more interesting than those in which a fatty or resinous 
matter is produced. They may be contrasted with the produc- 
tion of oily matter in living vegetables, and with the conversion 
into adipocere in dead animal matter. The most recently pro- 
duced secretion of a sebaceous follicle is nearly or quite aqueous, 
but it soon appears to be albuminous or caseous, and. does not 
appear to possess any oleaginous property. This it soon after 
acquires when it becomes the natural unguent to the skin. 
When the secretion fails to escape it accumulates, and a col- 
lection of grumous fatty matter is formed. In the early embryo 
the situation of the adipose substance is occupied by small grains 
of an opake whitish substance, which appears to be rather al- 
buminous or caseous than truly adipose. The production of 
cream in the lactiferous glands, when the milk is allowed to be 
well formed, appears to be another physiological instance. The 
next is of a pathological character. It is well known that in or 
near the ovaries it occasionally happens that encysted masses are 
found, containing fat, bone, teeth, and hair. Although the 
whole of these materials are not necessarily found in the same 
specimen, fatty matter appears to be invariably present. These 
extraordinary productions are generally referred to conception, 
and are indisputably closely allied to, if not identical with, it. 
Now in the natural ovum but a comparatively small portion of 
fatty matter exists, and certainly none in the situation in which 
the peculiar fatty matter which forms so large a portion of these 
encysted formations is met with. It would therefore appear 
that when growth as well as development has been suspended 
in these irregular efforts of the nisusformativus, there commences 
a conversion of the collected elements into a fatty substance by 
the introduction of anew chemical arrangement of the elements. 
Even this change is progressive, and it would appear that the 
fatty matter when formed is susceptible of further change ; for 
in some of these collections the fatty matter appears clean, 
nearly white and uniform; in others it approaches the character 
of cholesterine ; and in one instance we have met with it, having 
a bright yellow colour, and astrong, penetrating, empyreumatic 
or bituminous odour, bearing considerable resemblance to an 
unctuous yellow substance, found as a mineral production in 
Scotland some few years since, and placed in the possession of 
