Red pigment found laterally, and ventral to the eyes on both sides of competent
veligers and newly metamorphosed slugs, began to extend posteriorly in a line of red dots as the juvenile slug elongated (Fig.
For individuals from family P1, mean normoxic [??][O.sub.2] of fertilized eggs was 40% and 65% of [??][O.sub.2] of mid-veligers (56-74 hpf) and early benthic
veligers (146 hpf), respectively.
sitkana deposited egg masses in the laboratory, and
veligers of L, saxatilis were dissected from brooding females.
As with the findings of Koike (1978) in Haliotis tuberculata, cephalic tentacles, foot, and operculum appearance were noticed in posttorsional
veligers in H.
This ventral lip tubule is very similar to what has been described as the rudiment of the accessory salivary gland in encapsulated
veligers of Nucella lapillus and Conus anemone (Ball et al., 1997b; Ball, 2002).
Typically, approximately 60%-80% of the initial stocked larvae emerge as healthy
veligers. Survival during this phase is dependent on a stocking density of approximately 2-3 individuals/ml.
For our study, we chose to examine the effects of temperature on hatching proportions, as temperature has well-known effects on development time and thus could likely also influence the quantity of hatched
veligers versus juveniles in a poecilogonous species.
D larvae had an average length (L) of 71.9 [micro]m, remaining at this stage until the 5th day, when first umbo
veligers appeared (L = 115.9 [micro]m).
cementarium, is consistent with some observations on mollusc
veligers (Strathmann and Leise, 1979; Gallager, 1988), but captures within that zone may not represent the maximum capability of mollusc larvae or of larvae of S.
Most larval indicators were significantly influenced by sampling date (H = 32.1 for number of trochophores; F = 4.74 for diameter of trochophores; H = 29.3 for number of
veligers; F = 35.1 for diameter of
veligers), but not by depth of residence (H = 0.7 for number of trochophores; F = 1.24 for diameter of
veligers).
Our hypothesis was that
veligers can reduce captures per encounter between particle and cilium, thereby dissociating swimming and particle capture, even while both prototroch and metatroch beat.
After 72 [+ or -] 1.53 h, the encapsulated
veligers were in the post-torsion stage with a thickened shell and a very thin and transparent operculum.