Discovery reports (1936) Discovery reports discoveryreports12inst Year: 1936 3o6 DISCOVERY REPORTS naked specimens is very diflrerent from that of the grain-covered ones, there can be no doubt that they are only individual variations, the other characters being identical, and all intermediate stages being found. The supplementary dorsal plate may be very regularly developed, or it may be found only here and there (Fig. 33 b, c). The lateral plates may leave a space between them in the ventral midline, but the ventral plates remain just as widely separated as where the lateral plates join com
Discovery reports (1936) Discovery reports discoveryreports12inst Year: 1936 3o6 DISCOVERY REPORTS naked specimens is very diflrerent from that of the grain-covered ones, there can be no doubt that they are only individual variations, the other characters being identical, and all intermediate stages being found. The supplementary dorsal plate may be very regularly developed, or it may be found only here and there (Fig. 33 b, c). The lateral plates may leave a space between them in the ventral midline, but the ventral plates remain just as widely separated as where the lateral plates join completely. The genital slits vary somewhat in length, but they hardly exceed a length of 0-5 mm., and are often only half that length; there may be some granules at the slits. The adoral plates are excluded from the genital slits. The arm spines are three or four. This species is viviparous and hermaphrodite, but not a protandric hermaphrodite. Even at a size of 3 mm. diameter the gonads are hermaphrodite. In such young specimens Fig- 33- Opbiolebella biscutifera (G. A. Smith). Part of oral side {a) and dorsal side {b-c) of two different specimens, one without, the other with granules, xio. there is only one gonad in each bursa, placed at the interradial side. At a size of 4 mm. diameter also an adradial gonad is present; this latter gonad would seem to be male at first, the young eggs appearing therein a little later than the sperm cells. At a diameter of 7 mm. there are two gonads at the interradial, one at the adradial side of the bursa, all of them containing both male and female genital products. At this size young ones are found in the bursae; I have found no more than three young ones in a specimen, but of an extraordinary size, up to 2 mm. in diameter of disk. It is difficult to imagine how such large young ones can get out through the minute genital slits, only 0-5 mm. long. What a squeezing they must undergo, in spite of their rather large, compact scaling. It would
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