4 Echin. 
Xiy, ECHWODERMA, 
[1905] 
The numbered titles belong to the following years : uncertain, 2 ; 1890, 1 ; 
1893, 1 ; 1894, 3 ; 1895, 1 ; 1896, 1 ; 1897, 2 ; 1898, 5 ; 1899, 4 ; 1900, 3 ; 
1901, 10; 1902, 10; 1903, 18; 1904, 35; 1905, 284; 1906, 1. The number 
284 for the titular year has previously only been exceeded by the 288 of 
1903, for which year we now know of 335 works. It is therefore probable 
that over 50 works remain to be recorded for 1905. 
-II. Biology. Although no work is conspicuous for either extent or 
fundamental character, several minor problems receive solutions while 
others are brought into prominence. 
Anatomy. — In Woodland’s account of spicule-formation in Echinus 
(344) the point of chief interest to us is that the spicule does not begin 
as a tetrahedron but as an intracellular granule which becomes triradiate. 
The axial organ and ovoid gland of echinoderms have long afforded matter 
for controversy. Not unnaturally, since Pietschmann (256) discussing 
the varied histology and functions of the axial organ in Asteroids, and its 
connection with the oral blood-lacunae and with their radial extensions, 
proves that here as in crinoids different organs are confused. For Isocrinus 
these have been disentangled by Beichensperger (267), who has been 
able to prove by excellent material of L decorus that an adoral cell- 
complex, distinct from the glandular portion of the axial organ, but 
intimately connected with the labial blood-plexus, manufactures lymph - 
cells, which wander radially outward to the genital rachides of the arms 
and pinnules, becoming gonads on the way. His paper contains other 
interesting additions to our knowledge. Holothurians have no axial organ, 
but one seems to recognise something similar in Busso & Polara’s (283) 
statement that the formation of gonads in Phyllophorus and Strongylo- 
centrotus is accompanied by a development of supporting and glandular 
cells, which latter nourish the gonads. Polara (258) further shows that 
in Phyllophorus the • bilateral symmetry of the genital caeca is not 
accompanied by corresponding symmetry of the genital lacuna and aboral 
sinus as is the case in Synapta. 
By consideration of previous observations and by observation of un- 
stalked Crinoids preserved in alcohol, Minckert (214) confirms the views 
already expressed that the hypozygal and epizygal are complete brachial 
elements (Bather 1892, Bosshard 1900), and that the syzygy assists 
autotomy and provides a base for regeneration (Walther 1886, Bather 
1896, 1900);- he divides regeneration of brachia into simply reproductive, i.e. 
reproducing the branch as it existed before amputation, and augmentative, 
i.e. increasing the number of branches by the introduction of axillaries ; 
to the latter he ascribes the origin, both phylogenetic and ontogenetic, 
of all bifurcations beyond the first ; thus, species with more than 10 finial 
series (to which he restricts the term “ arms ”) owe the increased number 
not to nonnal growth, but to amputation, presumably autotomous, and 
augmentative regeneration. It remains for future workers to prove or 
disprove this ingenious theory by cultivating some many-branched species 
from early stages onwards. 
Minor anatomical notes are scattered through the larger faunistic and 
systematic memoirs to be mentioned later. Among the smaller papers 
Bell (25) notes the restriction of podial pores to the proximal arm-region, 
with probable absence of podia, in Ophiozona , Qphmra , and Ophiolipus , 
and suggests search for a respiratory compound. Kiernik (154, 155) 
shows that in the echinoids examined by him the glandular epithelium of 
the pedicellariae is columnar in a single layer, that the poison emerges 
by a single opening, that there are both striped and unstriped muscle 
fibres, quite distinct, the former probably effecting the rapid movements. 
The structure of various Palaeozoic Ophiurids leads Bather (21) to suggest 
that the vertebrae of this class may be composed of two successive pairs 
of so-called ambulacrals. 
Physiology, Bionomics, Auxology. — Students of experimental morr 
