— 304 — 
Seguendo il Grassi, lo Snyder ritiene che: 
« Neoteinie or supplementary royal individuals are obtained from an arrested early 
stage in the development of the nymphs of the first form, or even larvae, as voung are kept 
in an undifferentiated state, which can be speedily turned into reproductive forms that 
serve as substitutes » (pag. 68, 198). 
Osserva anche direttamente, trasportando un tronco lontano dalla sua sede, che 
la colonia può produrre sessuati neotenici a qualunque stagione, ognì qual volta ne 
abbia bisogno {!} e fa un diagramma dello sviluppo delle caste nel L. flavipes (pag. 36) 
uniformandosi a quello tracciato dal Grassi pel lucifugus : 
EGGS 
Ioung, undifferentiated larvae 
| 
| 
Large headed larvae. Larvae that will mature sexual organs. Reserves for ‘emergency repro- 
Las ductive forms. 
| | | 
Nymphs of the Nymphs of the Reserves for emergency repro- 
first form with 
long wiugs pads. 
second form with 
short wings 
pads. 
ductive forms. 
Winged pigmen- 
ted sexued adults. 
The true royal Nymphal neotsi- Nymphal e- Larval emer- 
pair with wings nic substitutive mergency gency substi- 
stubs. reproductive substitutive tutive repro- 
reproductiv e ductive forms. 
forms. 
forms. 
Ma nel 1917, studiando sul Reticulitermes favipes, €. B. Thompson distingue, in 
base a caratteri strutturali interni, già alla nascita il tipo riproduttivo dal neutro e poco 
dopo nel primo casta di prima e seconda forma e più tardi nel secondo operai da soldati (?). 
(1) « These forms can be produced at any time necessary. On April 9, 1912, a decaying stump 
infested with Aavipes was removed from the forest and placed in the termitarium ; this was at a time 
when the nymphs cf the first form were nearly mature. On November 18 the termites had entered 
the ground and two neoteinic ergatoid (?) forms were found about 3 to 4 inches below the surface 
in chambers in the earth. No nymphs of the first form were present. They could be distinguished from 
the workers by the larger size, distended abdomen, straw-colored pigmentation, and sharper segmenta- 
tion of the abdomen. Rudimentary wing pads were present. The antennae had 15 to 16 segments. 
Workers solicited drops of liquid from the female by stroking the abdomen with their palpi» 
(pag. 44, 198). 
(2) « The newly hatched nymphs of L. flavipes and L. virginicus are externally all alike, but 
internally they are marked structural differences which divide the nymphs into two sharply defined 
types, the reproduetive and the worker-soldier types, which are respectively the prototypes of the 
small headed and large headed nymphs of Grassi. Therefore, the fertile and sterile types are predetermi- 
ned at the time oî hatching. 
2. « The two types of newly hatched nymphs may be distinguished by the following characters; 
