The interstitial space is filled with hemoblasts.Under the microscop,the endothelial cells,at their non -nucleus sections,have processes extending to caecums.

• 光学显微镜下，淋巴器官由许多封闭的盲管构成，盲管腔主要是内皮细胞和基质细胞，胞间隙充满大量血细胞；