31. Feeding zooids are borne either evenly around the branch circumference or are absent from one face. 32. A pair of luminescent organs is on either side of the inlet siphon of each zooid . 33. A colony consists of a number of zooids which bud off from a long slender stolon. 34. Each individual zooid is a hermaphrodite. 35. The outer surface of the zooid is known as a tunic and is gelatinous and translucent. 36. Solitary zooids usually measure in length. 37. All post-Palaeozoic cyclostomes have interzooidal connections via pores in the vertical walls separating adjacent zooids . 38. The structure of the individual zooids is generally simple, with an uncalcified, flexible frontal wall. 39. Growth occurs by new rings of zooids being budded off around the edge of the elongating colony. 40. Each colony is entirely formed by the asexual reproduction of this founding zooid and subsequent clonal budding.
