104 



PROFESSOR ALLMAN ON THE GENETIC SUCCESSION 



pedicels along the sides of a long common peduncle, which springs from the 

 body of the hydranth. Their order of development, however, is centrifugal, or 



Fig. 5. — Diagram of Tubularia indivisa. 

 a a, hydranth on its stalk ; b, shortly stalked gono- 

 phores borne on a common peduncle, and increasing 

 in maturity from the proximal to the distal extremity 

 of the peduncle. 



Fig. 6. — Diagram of Tubularia larynx (Female). 

 a a, a hydranth on its stalk ; b, gonophores at- 

 tached by short stalks to a common branched 

 peduncle, and increasing in maturity from the 

 proximal to the distal extremities of the 

 branches. 



from the distal to the proximal extremity of the peduncle, so that the whole 

 group may be compared to a reversed raceme. In the female colonies of Tubu- 

 laria larynx (fig. 6), and in Corymorpha nutans, the pedicels become branched 



Fig. 7. — Diagram of Eudendrium. 



aaaaa, hydranthal zooids of the direct line of succession ; a'a'a', hydranthal zooids of a diverging line ; 



b b, suppressed hydranthal zooid, bearing gonophores, which are disposed in an unbelliform group. 



with a similar order of development, which thus gives us the compound re- 

 versed raceme or cyme. 



In certain proliferous medusae, the buds are borne on the manubrum with 





