56 EX VIRIBUS VIVIMUS. 



VERMES (Worms). — Turbellaria, unknown longevity ; they have itore 

 than a year's life. 

 Parasitic forms have interposed periods of quiescence (encysted 

 Toenia solium and Trichina), but die on reproduction. 



* Rotifera die yearly or half-yearly in some cases consequent on 



reproduction. 



ANNULATA (Ringed Worms). — None but a mechanical limit to life is 



' apparent. From the rate of grovpth and size, many years 



of life are inferred for Lumbricus, Eunice, Aphrodite, and 



Ampbinome. The smaller but not the larger Oligochseta 



die in vrinter after reproducing sexually. 



CRUSTACEA. — The larger forms (fiecapoda and some Schizopoda, also 

 Merostomatd), from their great range of adult size, are in- 

 ferred to continue growth long after sexual maturity, and no 

 period of natural decay is known to be reached. 

 Smaller forms ; many die annually, in the same way as Rotifera. 



* Cheirocepbalus diaphanut developes from the egg, reproduces, and 



dies in 2 to 3 months. (Observed by the writer.) 



* Cancer pagurus, of great size, was observed with adherent Cirrhi- 



pedia, which must have become attached subsequently to the 

 last moult, and have taken some years in their own growth. 

 (Communicated by Thomas Bell, Esq., F.R.S.) 



INSECTA. — The Imago, as a rule, lives part of a year — from 6 months 

 to a few hours — dying on reproduction. The length of life 

 of the larva varies greatly in closely allied forms, from 4 

 years or more to a week. (Coleoptera, Diptera.) 



* Rose-chafer (Scarabaeus auratus) was kept and observed 4 years 



in larva and 2 years in imago. (Leo Grindon, ' Life, its 

 Nature,' &c.) 



* Vanessa Cardui, usually observed to die at the end of the year, 



was kept by a lady 3 or 4 years. (Rev. J. G. Wood.) 

 ? Mantis religiosa is said to attain 8 years of life. (Leo Grindon, 

 loc. cit.) 

 Butterflies which escape copulation are known to hybernate and 

 live a second year, or part of it, as imagines. 



* Flea, 9 months in imago. A man is now in London with per- 



forming fleas, and he finds that 9 months is a very great age 

 for them to attain. 



