PLATE LIII. 



Figs. 1-0. Metagrinus tuberosus, n. sp. 



Fig. 1. Portion of the stem, ..... 



Fig. 2. Lower face of a supra-nodal joint, 



Fig. 3. Upper face of a nodal joint, .... 



Fig. 4. An ordinary internodal joint, . . ... 



Fig. 5. Lower face of an infra-nodal joint. 



Fig. 6. Side view of a nodal joint and the two upper joints of the in- 

 ternode below it, . 



369 



Figs. 7, 8. Rhizoceinus rawsoni, Pourtales. 



Fig. 7. A young specimen with the arm-bases slightly displaced at the 



syzygy between the first and second brachials, . . x 20 



Fig. 8. The upper part of the stem, with the calyx and first l^rachials 



of a slightly older individual, . . . . x 20 



265 



266 



