248 
DE. E. KLEIN ON THE SMALLPOX OP SHEEP. 
Fig. 12. From a section of the subcutaneous tissue of the same pustule as fig. 11 
(oc. 3, obj. 8), showing: — 
A. The distended interfascicular lymph-spaces. 
B. Connective-tissue corpuscles in an altered condition. 
C. Bundles of connective tissue. 
Fig. 1 3. Section through subcutaneous tissue of a primary pustule from 3 to 4 days old. 
(Oc. 3, obj. 7.) 
A. Lymphatic vessels. 
B. Interfascicular lymph-spaces. 
C. Bundles of connective tissue. 
The lymphatic vessel and the interfascicular spaces contain Micrococci 
either in the form of zooglcea or of necklaces. 
The lymphatic vessel is lined with endothelium. On the surface of 
the bundles of connective tissue the corpuscles are seen to extend 
into the interfascicular spaces. 
Fig. 14. Vertical section through the periphery of a primary pustule 10 days old. 
(Oc. 2, obj. 7.) 
A. Horny layer. 
B. Bete Malpighii. There is a striking difference in the thickness of the 
epidermis in the pustule and in the neighbouring healthy skin. In 
the former the rete Malpighii is divided into three parts by a middle 
horny layer, viz. a superficial layer and a deep layer which is under- 
going active proliferation, sending out long thick interpapillary 
processes. 
C. Superficial layer of corium. It is seen to be very different from that 
of healthy skin, being infiltrated with lymph-cells and having large 
papillse. 
D. A vesicle in the rete Malpighii, the lymph-corpuscle of which can be 
traced to have migrated from the papillae into the deep layer of the 
rete. To the left of the drawing small cavities containing lymph- 
corpuscles may he observed in the deep layer of the rete Malpighii. 
These are the first traces of the formation of vesicles. 
Fig. 15. Vertical section of the rete Malpighii below the middle horny stratum (see figs. 
6 & 14) from a primary pustule 12 days old. The epithelial cells are seen 
to be much enlarged, many of them somewhat dropsical and vacuolated and 
changed into vesicles of various sizes. They are confluent, and thus form 
channels. It may be observed that there is a migration of lymph-corpuscles 
from the lower portion (B) towards the surface (A). The highly refractive 
bodies contained in the vacuolated epithelial cells originate, probably, partly 
from the nuclei of those cells, partly from lymph-corpuscles. Some of them 
are of a greenish colour, and are contained in lymph-corpuscles. A granular 
