Various causes, such as increased predation pressure, the lack of planktotrophic larvae, a ‘resetting’ of diversity, increased competition from benthic molluscs and the decline of the Palaeozoic fauna, have been suggested to explain the failure of the brachiopods to reradiate following the Permo‐Triassic mass extinction. Increased predation pressure has hitherto appeared improbable, because typical predators of brachiopods, such as teleostean fish, brachyuran crabs and predatory gastropods, did not undergo major radiation until the late Mesozoic and early Cenozoic. However, new evidence strongly suggests that one important group of predators of shelly benthic organisms, the asteroids, underwent a major radiation at the beginning of the Mesozoic. Although asteroids appeared in the early Ordovician, they remained a minor element of the marine benthos during the Palaeozoic acme of the brachiopods. However, these early asteroids lacked four important requirements for active predation on a bivalved epifauna: muscular arms (evolved in the early Carboniferous); suckered tube feet, a flexible mouth frame and an eversible stomach (all evolved in the early Triassic). Thus radiation of the Subclass Neoasteroidea coincided with both their improved feeding capability and the decline of the articulates. The asteroids were the only group of predators of brachiopods that underwent a major adaptive radiation in the earliest Mesozoic. The asteroids may therefore have contributed to inhibiting a Mesozoic reradiation of the brachiopods. Epifaunal species lacking a muscular pedicle may have been particularly vulnerable. Unlike bivalve molluscs, modern brachiopods show only a limited range of adaptations to discourage asteroid predation. □Asteroidea, Brachiopoda, evolution, predation, functional morphology.

New interpretations of morphology, new occurrences and new taxa of British Silurian cystoids are summarized. Two ambulacral patterns occur in the Callocystitidae. In one the first two brachiole facets branch to the left in ambulacra B and D, but only the first one in ambulacra A, C and E (the B þ D arrangement). In the alternative pattern all ambulacra are the same with only the first brachiole branching to the left. The B þ D pattern is plesiomorphic. Among callocystitids with four ambulacra the type species of Tetracystis has the B þ D arrangement as does 'Apiocystites' elegans; both are referred to Tetracystis. The British species 'T.' oblongus has all ambulacra the same and becomes type species of the new genus Troosticystis. New records include Homocystites brenchleyi sp. nov. from the Rhuddanian of South Wales, which demonstrates that the family Cheirocrinidae did not become extinct at the end of the Ordovician as previously suspected. The British Silurian cystoid Prunocystites fletcheri has been recorded from Norway, the only species known to occur outside Britain. Schizocystis armata (Forbes, 1848) occurs at a new locality near Buildwas, Shropshire. Glansicystis glans sp. nov. is described for 'the common form' of G. baccata. It differs from G. baccata in having a larger oral area, weaker thecal ornament, shallower plate sutures and a more cylindrical theca.

The first terrestrial arthropods recorded from the Jamaican fossil record are millipedes (Diplopoda), representing at least three species, from a late Pleistocene or Holocene cave deposit. Taxa identified include Rhinom'cus sp. or spp., a& Chondrotropis sp. and Caraibodesmus verrucosus (Pocock). The associated fauna includes diverse vertebrates and gastropods, with rare isopods, nonmarine crab claws and ostracodes. Preservation of millipedes has been enabled by calcite coating, lining and impregnating the chitinous exoskeleton, which had a high original calcium content and acted as a nucleus for precipitation. Delicate structures such as limbs, antennae, gonopods and eyes may all be preserved. This preservation has been facilitated by the bottle-shaped cave with an opening at its apex, the surrounding limestone, the clastic infill, and the seasonality of precipitation with very high rainfalls during tropical storms and hurricanes. Millipedes most probably drowned in the cave during storms and formed a nucleus for the precipitation of calcite from solution. This suite of conditions is most likely to occur in the tropics.

Unmedicated depressed outpatients were tested on dichotic syllable and complex tone tests prior to receiving 16 weekly sessions of cognitive therapy (n = 31) or 6-12 weeks of placebo treatment (n = 45). Cognitive-therapy responders had twice the right-ear (left hemisphere) advantage for syllables when compared with nonresponders but did not differ from nonresponders on the nonverbal task. The larger right-ear advantage in cognitive-therapy responders was due to better right-ear accuracy; they did not differ from nonresponders in left-ear accuracy. No differences in perceptual asymmetry or accuracy were found between placebo responders and nonresponders. Right-ear accuracy for syllables was the best predictor of response to cognitive therapy in a logistic regression analysis. The findings suggest that greater left-hemisphere advantage for verbal processing is associated with more favorable outcome of cognitive therapy for depression.

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